34th America's Cup: multihulls!

The answer is YES.

 

34th AC

Looks to me that LR hangs with and may be a bit faster than NZ in this poor quality video-esp. near the end.
http://www.youtube.com/watch?feature=player_embedded&v=mhfKvWLvENc

 

LR is sailing a much higher angle downhill, (carrying 2 sails) looks faster - but isn't - to the next mark.

 

34th AC

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During the whole vid TNZ is carrying a jib and screecher(?) but LR only one jib-unless my eyes are deceiving me?

 

34th AC

Great picture of TNZ:

click-

 

34th AC

Here's another poor quality video that definitely shows TNZ pulling away from LR:
http://www.youtube.com/watch?feature=player_embedded&v=IL7PQf7vmMg

 

LR was just playing possum... just wait and see!

I may be biased, I'm an LR fan.

 

34th AC

Raps,good for you! I guess I'm rooting for everybody some of the time and Oracle primarily and Artemis next.

 

34th AC

From Scuttlebutt last night:

FOIL FOCUSED

Behind the scenes at Oracle Team USA, Joseph Ozanne crunches numbers using
mind-numbing equations all in the name of a faster time around the
racecourse for his team's AC72. Ozanne is the team's wing design leader and
is also responsible for the performance prediction functions.

Much of his work in the current campaign involves the daggerboards, which
he believes will be critical to a team's success in the 34th America's Cup.
Now on his third campaign with Oracle, the 34-year old Frenchman has had
plenty of experience working with the best in the game.

Is the wing more important that the foils on the 72s?

"No. You need to consider that the foils are now the main driver of
performance on these boats. It's critical to have it right. Last Cup I was
a wing designer, and then everybody believed that the wing was the key but
that's not true. The reality is that on this boat, the multihull, we try to
minimize the drag. That's the goal overall. Where you can really make big
gains is under the water, and you really need to have it correct. The foils
and the windage are two areas where you have to focus because boats are
going 40 knots, and the faster you go [the more] you're going to create
drag. The most efficient way to do that is to lift the boat to reduce the
volume of the floats, so you need to lift your boat out of the water. You
can do that with foils, but you can't do that with the wing because it is
vertical."
Sailing World, full interview:
http://www.sailingworld.com/blogs/racing/americas-cup/foil-focused

 

Canting wings and foils?

 

A-Class cat foiling - There is discussion and some shots of a "flying" A Class. Is flying legal in A Class? It use to be not allowed? Rule 8 says hydrofoils are not allowed... Rule 10 says hydrofoils are allowed? Does anyone know what the current interpretation is? Its fine to build an A Class that can fly but its another thing to fly in a race (which may not be allowed). eg The current AC rules were written to inhibit flying. They stopped short of saying "no flying" for whatever reason and constructed a rule that resisted it. But as usual clever people find ways around the rules so now we have flying. The C Class experience is that flying is not faster around a course (overall) but then it was the first serious attempt at it. But can someone comment on the A Class situation? Regards Peter S

Tomas - yes water is 800x denser than air so its requires a much smaller area to produce the same lift. Lift = Cl/2 x Area x density x velocity squared.

 

Hi Evan - Yes we seem to be at a technological impasse until we get these boats lined up side by side. So what is an area we have not discussed that we are missing? Seems we are not interested in talking about "sailing mechanics" which is the area concerned about how the sailors use their equipment and how they move around the boat. We have not discussed how many options there are in the foils. The rules allows 5? foil sets from memory? The teams will have to have a quiver of them and make a decision on the day to which set they use. Perhaps they even may use a different one on each side to help account for tide? They are using different ones now so they can compare on the water differences. The platforms are all quite different and all seem to be reliable. (OR wobble aside) Artemis have a central cockpit which maybe really useful in this tight racing. The Rm penalty of not having crew on the hull maybe offset by the time saved in manouvours? I've always wondered how the helm changeover responsibility is taken in this class. ie someone has to be on the helm on the otherside before the "captain" changes over so are they jointly responsible for a cock up? The wing is a very subtle object. We just see it sitting up there but we are new to wing sailing and there are huge zones of performance that we don't really know about yet. This is due to the extra control we have over a wing. Especially in the camber/twist area. The flight envelope is much bigger and less known for these things. What happened to the platform end plate & the wing extension on OR 17.1.0? Will we see this again on 17.2.0? We are about 4 weeks away from TNZ and LR headfing for SF so it will get more intense very soon. Bring back some tech talk. Peter s

 

Peter, it is legal to fly in the A Class, though the rules were changed some time back to make it "impossible". Sound familiar? The foiling no-camp will probably rise again because on March 4th, 2013 Dario Valenza announced that his Paradox(see thread this forum) was foiling stabley on class legal foils designed by Martin Fischer. Of course, as you say, the history of foiling cats is not good-just because it is foiling doesn't mean it is faster than other A Class cats. I think it is a tremendous development and I hope Dario can get it to be fast.
Many of the A class builders are offering rudder foils to work with the "standard" curved foils. Foiling is definitely in the air unless the boogey men are able to change the rules once again.
http://www.boatdesign.net/forums/multihulls/dario-valenza-stable-foiling-class-cat-46468.html

Peter, take a look at the new D3: http://www.d3-a-cat.com/#

 

If foils are regulated out then someone will just start a new series that allows foils. The bottom line is money is what keeps all boats moving. Money comes from sponsors and sponsors want image and ad sales to the general public. Pictures and videos of fast exciting foilers are easier to sell to the public than old and slow.

 

To foil or not to foil... is that the Question? It seems to me that the rule makers and sailors need to get together and make some decisions which would save the industry and everyone lots of time, energy and money. If a class is to allow foiling then we need to allow trimming devices. We have spent a hugh amount of time and effort to acheive flying with very crude devices in classes that basically oppose it. We have been flying very successfully for double decades in boats that are designed to fly. Curved foils are complex, unpredictable and limited. We only go down this path to circumvent the rules. The rules are generally designed to control cost but ultimately they increase cost. If we rationalised some of the rules and allowed conventional trim tabs on convention hydrofoils we would be flying cheaply and successfully. Unfortunately foiling has limits and once we hit those limits the next level will kick in and the discussion will continue. At 30kn or 40kn do we allow lifting aerofoil surfaces? An A Class has enough platform to be quite a nice aerofoil at those speeds so then we will be talking about in-ground effect control (who votes for carbonworks in-ground effect A Class?). We still have not had the discussion about electronic device control. We can't drive a car now without these and certainly every race car has oodles of electronics that allow it to go faster. So do we allow GPS height control? These are big questions for the industry to deal with into the future. I have recently used Google trends to do some industry analysis and Sailing as a sport my friends is dying. In the next 20 years it may cease to exist. The partipation rate is going down, the industry value is going down, every indictor is going down. Other sports are level or doing better. We need to step up to attract people or the industry like valves and cathode ray monitors won't be around soon. Peter