Americas Cup

[bobthebuilder]

If you listen to the on-board audio on Britannia you will hear them saying “your wheel” on every tack and gybe, then you see Ben nimble round aft of the boom. I thought it was odd to start with but that’s how they free Scott up as full time tactician

Only Luna Rosa has a port and starboard helmsman. The others have a lead helm who hands over control to during an evolution whilst he moves to the new windward side.

 

[bobthebuilder]

@bobthebuilder you’re right, it was a baby stay, getting old. I remember the removable ones on the Nic55s. In this particular case, the baby stay was adjustable and was, or should have been, part of trimming the mast bend

Can’t say I’ve ever raced on a masthead yacht; I’ve never seen a baby stay being adjusted on the water. Every day is a school day.

The basics of rig tune for the uninitiated. The AC75 rigs are keel stepped fractional rigs.

How to Tune Your Rig | North Sails

Without a properly tuned rig, you won’t be able to control your mast’s behavior over the full range of conditions. Fortunately, rig tuning is a straightforward step by step process... Read More

www.northsails.com

 

[Saturation]

The UK team just won today's race and is now automatically in the Prada final.

 

[sniper_bob]

Great win for INEOS. To my untrained eye, INEOS had control issues with their cunningham so lacked a bit of speed downwind. Prada effectively lost the race with unforced errors, poor tacking etc. I don't think INEOS can expect that much generosity from NZL.

 

[Grownup_Rafbrat]

The UK team just won today's race and is now automatically in the Prada final.

No Ghost races then?

 

[sniper_bob]

Ainslie hedging his bets, saying they might not race tomorrow and reduce risk to the boat. Can't say I agree. Prada and American Magic have a further 7 races before the final and the more race time on the water the better. Also I'll be a tad disappointed to get up at 3am tomorrow and find there's no racing!

 

[Saturation]

No Ghost races then?

I know what you are saying, and that has been mooted, but team UK does not have to take part as they are now already qualified for the final.
I understand for the ghost race that if the US does not front, all the other team being the Ities, have to do to win is cross the start line.
What now happens remains to be seen.

 

[RumRationReject]

control issues with their cunningham so lacked a bit of speed downwind.

Sounds like a Viagra related euphemism.


Sorry, back to the sailing....

 

[bobthebuilder]

Great win for INEOS. To my untrained eye, INEOS had control issues with their cunningham so lacked a bit of speed downwind. Prada effectively lost the race with unforced errors, poor tacking etc. I don't think INEOS can expect that much generosity from NZL.

The cunningham pulls down on the luff of the mainsail, vertically, parallel to the mast. It applies tension to the luff (the front of the sail), which, in turn, controls how far forward or aft the maximum cord dept sits.

Absolutely critical sail control on a rig like this; it controls power downwind. These boats never really sail downwind; the apparent wind is always forward of the beam. Apparent wind being the “wind” you feel because you are going forwards.

On cruisers and cruiser racers, the halyard (pulls the sail up the rig) can be used for coarse adjustment; on these boats the halyards are pulled up in to a lock and luff tensions is entirely adjusted with the cunno.

 

[sniper_bob]

INEOS TEAM UK WIN THE PRADA CUP ROUND ROBINS

PRADA CUPINEOS TEAM UK jump to the PRADA CUP Final

www.americascup.com

And the very last line of the update..... "No races will be held tomorrow". Bit of a cop out having had to go through the formality of 2 ghost races today.

 

[bobthebuilder]

Watched a very techie video today about the wing design. Basically, it was suggesting that before Christmas Ineos appeared to have gone the wrong way with their wings. But now it looks like they’ve gained an advantage.

Ineos has delta shaped wings; they look like a Vulcan bomber. All of the other boats of long, narrow wings like a glider.

Hydrodynamics suggest that the delta wing is the wrong way to go; they only well work at high speeds. At low speeds they are unstable and very difficult to control (think Typhoon winglets, computer controlled). So Ineos couldn’t get up onto her foils in the Christmas Cup because their control systems weren’t working properly. To make matters worse, the wings were taking in water; watch videos of them sailing before Christmas and water streams out of the wings as they are raised.

The up side of delta wings is that they have a bigger internal volume, so bigger hydraulic rams for the tabs are operating direct (the rams are fitted fore to aft). On the long thin wings, the smaller rams are at 90 degrees to the hull and drive through a gear.

Delta wings also give more lift at high speeds. They suggested that at speeds of 45kts and above, Ineos will have a distinct advantage.

The core conclusion amongst lots of boring conversation about Reynolds Numbers is that Ineos may have stolen a march. They’ve solved the water ingress issue and have developed software to control the tabs that works quicker than a human can. The suggested differentiator is Mercedes at Brackley.

I’ll post the video if I can find it again! Meantime, check out the wing shapes.

 

[sniper_bob]

American Magic show off rapid repair work following Prada Cup capsize, and note of thanks to those who helped

The boat featured a large band-aid graphic on the hull saying "thank you" to rivals who helped out on the water.

www.tvnz.co.nz

Nice touch from American Magic. Good to see them back on the water with semi-finals starting on Friday.

Meanwhile NZL are testing a new set of foils and Jimmy Spithill's getting ready to file a technical protest against INEOS (if you can't beat them on the water, try the legal route - seems typical).

 

[bobthebuilder]

I’m beginning to think that Ineos’s grinder set up is a significant innovation.

Apparently, grinding forwards on a one-man pedestal gives 20% more power per man than doubling up and having one man going backwards. Plus the grinders are only providing energy for the above deck activities ie sail trim. Everything below deck is electric, which is not the case for some of the boats.

Add in the fact that their grinders’ conditioning program has been developed by the Ineos Grenadiers cycle team and the hydraulic manifolds by Mercedes F1, of which Ineos is a 1/3rd owner and you have six grinders doing the work of 8 on the other boats. The synergies across Ineos’ sporting activities are significant.

One man pedestals mean the grinders can face outwards rather than forwards / backwards. This means they can be crammed in forward, where their weight is more effective. Six grinders frees up Giles Scott as a dedicated tactician. Clever stuff.

Beyond the Cup: Freddie Carr on Ineos Team UK's grinders - NZ Herald

INEOS Team UK Grinder Freddie Carr reveals the team's unique approach to grinders onboard. Video / NZME

bit.ly

Beyond the Cup: Freddie Carr on Ineos Team UK's grinders - NZ Herald

INEOS Team UK Grinder Freddie Carr reveals the team's unique approach to grinders onboard. Video / NZME

www.nzherald.co.nz

 

[Saturation]

The Ities have just thrashed the USA in the first round robin race by 2 min 43 secs.

 

[Saturation]

Race two today Italy comfortably wins again by 3mins 20secs. Two more races tomorrow and it should be all over for the US.
There is something wrong with the US boat, they can't control it, it has almost tipped over four times today.

 

[sniper_bob]

From the commentary and on board comms it certainly sounded like a rudder problem, losing grip on the fast bear-aways. On the other hand Luna Rossa looked slick and in control throughout. I thought Spithill should have competed harder for the second start, they were in a good position but just seemed to back off from the challenge. As you say, all over tomorrow.

 

[bobthebuilder]

From the commentary and on board comms it certainly sounded like a rudder problem, losing grip on the fast bear-aways. On the other hand Luna Rossa looked slick and in control throughout. I thought Spithill should have competed harder for the second start, they were in a good position but just seemed to back off from the challenge. As you say, all over tomorrow.

They fitted a new rudder whilst they were rebuilding. Looked to have a very small section compared with the other boats and their previous rudder. They’re all running deep rudders with a very small section to minimise drag, but maybe AM have gone just too far.

Wind speeds today were right up near the maximum limit for racing. Presumably they need more rudder power at those speeds, especially when it’s gusting (clocked at 53kts today), base wind was 20kts today, gusting to 30.

They had problems with the new rudder ventilating on Wednesday and HD a near miss when the bow went up and the boat dropped off its foils

 

[Saturation]

Italy wins 3rd race in semi-final comfortably by 33 secs.
Looks increasingly like an Italy/UK final.
The next race starts in about 30 minutes.

 

[Saturation]

She's all over for the US.
They kept losing control and sitting down in the water.
Italy crossed the line at least 3 km in front.
US can now pack up and go home.
UK/Italy race off in the final of the Parada Cup.

 

[Queensman]

Fair play to the Italians, I think they’re going to present Sir Ben with a few problems in a fortnights time. Never easy to see a team do so badly (unless it’s Bath! 48-3 hahaha....but that’s another story), one has to feel for the Americans. A fantastic effort getting back on the water after the prang but clearly, Patriot had problems from the start. Sad. Especially so because the Boat Captain is an old sailing mate of mine.
Back to following the wonderful Pip Hare in the Vendée for a few more days. (Does anyone know what Armel Tripon is up to?).