34th America's Cup: multihulls!

In reading the descriptions of the Oracle gizmo, I was struck to the similarity of its logic to that of an automatic sail trimmer devised by Francis Reynolds and described in the attached. In the Oracle case the role played by Reynolds' vane is taken by the trimmer's handle. Reynolds was a Boeing engineer -- I wonder if Tom Speer ever met him? Almost certainly all a coincidence, but an interesting one.

In any case, the Oracle designers taught the ETNZ designers the same lesson that the Wright Brothers taught their competitors: thrust and lift are relatively easy to achieve, control is the tricky part.

Cheers,

Earl

 

First Foiling America's Cup

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Earl, did you watch any of the racing? Did you enjoy it?

 

I do not know if I can use another similarity here, but I will try it. Do you believe that this mechanism, which is not manual (*) ( whatever the blinded by the suspense and the final relief fans of US Oracle try to convince themselves...), is more akin to an automatic or to a semi-automatic gearbox ?

* An example of wishful thinking :

 

Cant say I've tried any of the Oatley Wines I'm more of a cleanskin man myself so I might have . Plenty of quality Aussie Sailors left to crew a boat even after Larry's garnishing of our talent. Hawaii in general has some decent seastates and solid winds which makes you wonder whether it would be a suitable venue for these apparent wind machines they might look very different to cope with the conditions. I guess also it depends whether Larry wants easy access for the public viewing of the races something which San Francisco Bay offered.

 

I believe that most people in this Forum are aware of the various automatic mechanisms that control the AoA of the foils... The first time I had learned that such mechanisms exist, was when I saw the beautiful diagram in p.113 of the classic Aero-Hydrodynamics of Sailing by Marchaj, 1979 - a reproduction of C Hook s idea of a semi-automatically controlled Hydrofoil Sailing Vessel - and this mechanism was devised 45 years ago ! Since then, I guess that many much more sophisticated such mechanisms have been developed with or without sensors on the water surface, which control the distance of the hulls above the surface and the pitching motion of the boat. And I have no doubt that we will see more of them in the next Cup, if they will not be prohibited by the new rules. It is amusing to listen to people trying to deny the more or less automatic character of them, based upon the fact that they do not use "stored energy" !

Enjoy :

"We weren't allowed to be automated. The measurers never would have allowed that." He added with a chuckle, "We were quite happy to have Team New Zealand believe that.
R. Coutts

We got more stable because we learned to fly our boat better. Just like ETNZ got more stable as they gained time on the water.
Tom Speer

 

The most obvious example of automatic trimming is the gust response built into dinghy masts. No one seems to have a problem with that.

A control system on the foil to react to loading is not very different than that IMO.

 

Theoretically, it is not very different, indeed - but as it becomes more complex, it is can not be considered as "manual" any more, even if, at some point, the trimmer "pushes an on/off button". I do not know if and how we can define where the "manual" becomes "semi-automatic" and the "semi-automatic" "fully automatic", but certainly the systems described in the previous posts do not "look" very manual to me...
What would have been a true "manual" system ? Something like a power-assisted rudder/foil, where the helmsman/trimmer of the rudder/foil decides ( in the true sense of the word ) and turns a tiller or a wheel, and, by this action, and at the same time, the rudder/foil turns, and its AoA changes. It would probably need a trimmer turning a second wheel and sitting next to the helmsman, so he can watch his actions, and can feel the pitching of the hull more than if he was sitting amidships.
However, it may be the case that such direct manual systems have been tried and proved to be unstable, and US Oracle decided to go for a more sophisticated mechanism, where there was some more or less automatic self-adjusting of the AoA of the foil, so the hulls remain horizontal. I am ot saying that TNZ had not considered, or even had not used a similar system - but it seems that, if they did, their system was worse, less sensitive, and evidently slower. During the last races, the TNZ boat was dancing, compared to the rock solid US Oracle boat ! I almost felt sorry for "poor" Dean Barker !

 

The easy way to avoid this in the future is to allow manual adjustment of either a trim tab on the main foil, the rudder, or both. Using the water to provide trimming force (as a wand on Moth does) is 100% within the spirit of the rules. As usual the attempt to keep costs down by limiting control surfaces, ended up increasing the cost and complexity.

There is also a question that could be raised about propulsion. Pumping and Ooching are banned kinetics, where do 6 all beef grinders powering a hydraulic system fit into the trim, vs kinetics scale?

I very much doubt that these boats and systems will be used again. There is little value in keeping the methodology secret. I hope that Tom Speer of someone else that *knows* how the system works will provide details for the curious amongst us.

 

Not really, gave up after a couple of LVC races. I'm engaged in a major, time-consuming project and just wasn't interested enough to take time away from it.

Cheers,

Earl

 

First Foiling America's Cup

Article from Yachting World: http://www.yachtingworld.com/blogs/matthew-sheahan/535348/america-s-cup-what-was-changed-on-oracle

One of the points in the article:
Hull interceptor
A vertical plate like device known as an interceptor was fitted to the transoms to modify the flow out from the stern and reduce drag. The system acts like a boot spoiler on a car and is a popular device on boats like Open 60s.

 

First Foiling AC

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You should watch some of the replays-Race 4,18 and 19....... http://www.youtube.com/user/AmericasCup

 

First Foiling America's Cup

From SA:

Funny (big surprise!), from here: http://www.nzherald....jectid=11132657

Sir Russell Coutts says the foil-adjusting technology rumoured to be the key to Oracle's comeback in the America's Cup was a figment of someone's imagination.
The Oracle chief executive said "Herbie" as it had been termed, was a beat-up.
"It would be illegal to have an automated system on board. It would not be allowed. The measurers inspected the boats before and after each day of use and they saw nothing.
"It's amazing how some so-called knowledgeable people started to believe in stuff like that."

 

I agree... I can not understand the reason ( if there was any...) that the writers of the AC72 rules had not allowed the use of such simple water-driven stabilizers, although they left the door wide open to much more complex semi-automatic SAS-like systems... provided they do not use "stored energy" ! That farce of the "stored energy" that is supposed to be what makes a system "automatic" or "computerized", while complex enough mechanical computing devices ( that do not resemble anything "manual" ) are known centuries ago, was so naïve... I could nt believe that a high-tech company would feel the need to hide the use of a self-adjusting more or less automatic foil control system, instead of advertising its use as an innovative break-through...
I have not made my mind yet, about how much automation I would prefer to be allowed in the next cup...The sight of the rock-stable Oracle boat flying towards the windward mark was magnificent - how one can retain it, while retaining the immediate, direct, manual control of the boat by the sailors, which is one of the great satisfactions sailing offers ?

 

It is amusing that Americans use the title "Sir" for Coutts ! All of a sudden, we are surrounded by so many knighted "Sirs". Rule, Britannia !
( Royalists in the Monarchy of New Zealand will feel so good with this...)

The measurers saw nothing ? So there was nothing to be seen. So, why you do not show the boat to the general public, "Sir " ? And if there is nothing there, indeed, you would be asked to use it as it is now, just one more time, and run a windward leg like the one you run at the last race !

So, we are asked to believe that all those differences the article in YW describes, which were already there right from the first race, suddenly, miraculously, or by divine intervention, paid off, all at the same time, after the 11th race ! ! !

Americans were so great when they were losing, and so little now they have won ! ( Ooops ! "Sir" is not an American ! He is just doing his job. )

 

I think the question of whether or not the Team Oracle boat was always the fastest boat is a legitimate one.

Losing two out of three races then winning eight in a row should raise some suspicions. Kind of like a pool hall hustle.

Most likely, LE sloped the design rules so much in his favor by specifying about the closest thing to one design he could get.

This, among other incidents throughout the AC's long history, only help to corrode its reputation.

These AC72's provided nothing for the sailing community other than a sloped battle between two plutocrats, which one man paid for with his life (due to a design requirement) to be in.

I see incredibly bad sportsmanship on the part of LE (in specifying an inherently unsafe design) and I take little pride in the US retaining the cup.

LE and Team Oracle may have never cheated in any real sense of the word, but, like the Kennedy assassination, the truth may not matter much, either way.

I think the terms of the "Deed of Gift" could stand some revisiting.