The Next America's Cup in Multihulls

America's Cup boat design shrouded in mystery

http://edition.cnn.com/2009/SPORT/06/15/alinghi.boat/#cnnSTCVideo

Alinghi America's Cup Catamaran unveiled

America’s Cup: the Alinghi catamaran, July 4. 2009

text HERE


...and a few photos in the tent

WOW , imagine the loads at those connection points between hulls and crossbeams...even without the huge rigging loads that will be applied!!

Report and Photos

Interesting report and interesting photos...some history as well

http://www.sail-world.com/USA/index.cfm?SEID=0&Nid=58599&SRCID=0&ntid=19&tickeruid=0&tickerCID=0

Check out that central fore-to-aft beam. I knew there had to be something like this being utilized, but it wasn't shown in those first photos. ...from a couple of years ago a discussion of their 40 foot lake racing model....Vessel Substructure to Support Rigging Loads

I believe it was quoted that they were bringing in a big Russian helo that can do the job...longer distance and greater altitude

James Boyd, Daily Sail:
The boat shares the same engineering nightmare as Team Phillips in that she has a rear and centre crossbeam, but no forward beam. This is to reduce weight forward and the alarming tendency catamaran forward beams have to slam into waves (unless freeboard at the bow is enormous- and thus heavy - as it is on for example Orange 2).

With the main central crossbeam around 50% of the way back from the bow this leaves a huge length of bow unsupported.and remember what happened to Team Philips. However in the Team Philips case the bow snapped off due to a build error that had resulted in the carbon laminate 'blowing off' the Nomex core in this crucial area. We suspect that given the exacting detail of the Swiss team's engineers and builders this will not be the case here. Nonetheless the unsupported bows remain a questionable area of her overall structure

I agree with you Fishtigua. Here is a little comment I added over on Sailing Anarchy:
You might notice I posted my original discussion of this unique vessel back in 2006.

Had I been following all of this America's Cup crap even loosely, I'd have made a bet it was something based on these cats he has been racing on Lake Geneva. So that wasn't so difficult to figure out, given the time constraints they were under.

I haven't let myself get too excited about this race as it was just so much legal bull****. And the last time I got excited about a multihull in the America's Cup (as I was in the business at the time), it came and went so quickly that I wondered what worth it was in promoting the multihull breed. This event will probably do the same...very little.
My contention at that time is that the NZ monohull could have been beat by a souped-up Stiletto 23...now that would have made a statement !!

What has truly propelled multihulls into mainstream is the French embrace of the vessels. I was there at the beginning, the Formula 40 racing class in France. Randy Smyth (with Cam Lewis on board) was the only American boat, and he did a great job representing the USA.

Too bad this race is about who has the biggest cock...rather than some real sophistication

Spy Duck

...this is funny...courtesy of Latitude 38


Before heading north to Newport and Catalina, we stopped by the BMW Oracle compound — which is located next to Joe's Crab Shack in downtown San Diego — to see what was going on. The biggest noticeable change since last November is that they brought the big white fabric building in which the 90-ft by 90-ft trimaran had been built down from Washington. Since the sophisticated tri wasn't anywhere in sight, we presume she was inside getting worked on. A short distance from the building were what appeared to be three massive carbon fiber masts.

From the outside, the compound looked pretty quiet. As we stood looking at the rather small BMW Oracle sign near the guard station, we were approached by a duck who was eager to talk. "If you're looking for a finely crafted German automobile or some world class enterprise software, you won't find them in that building," he said. "No, what's inside that building is the trimaran that's going to be used in the next America's Cup. Alinghi, the Defenders, don't have to announce where the Cup is going to be held for a few more months, but it has to be held by the end of next February."

Surprised to meet a duck with such an interest in sailing, to say nothing of having a fine command of the English language, we just nodded and let him continue.

"Last year they had the tri sailing at more than 40 knots, which would be fast enough to get my feathers ruffled. Given the speeds and loads, somebody could really get hurt. No wonder that principle helmsman James Spitall and the rest of the crew wear helmets and body armor. And that there are EMTs on the support boats that chase the big tri. There have been rumors around the nest that Larry Ellison, owner of the campaign, sailed on the tri once, and that was enough for him. What's even more telling is that Russell Coutts, the America's Cup legend, is rumored to be afraid of the boat, too. But I think that's just gossip, don't you?

"You probably want to know what they've been doing inside that building since they stopped sailing operations in February," said the loquacious duck without giving us time to answer his question. "I'd probably end up as Peking duck on the BMW Oracle crew menu if they knew that I told you, but they've been making a hard sail for the trimaran. Sort of like the one Dennis Conner used when his catamaran beat the Kiwi 'big boat' monohull in the funky America's Cup in San Diego many years ago. I also heard that something like $5 million was spent on either modifying or replacing the two outer hulls. If anyone is feeling sorry for syndicate owner Larry Ellison, they don't have to. My 401K for ducks has taken a beating in the last year, but not from Oracle. They had an operating income of almost $8 billion in the last quarter, and if I'm not mistaken, Ellison still owns something like 20% of the company. So he's not having to chase the America's Cup with a cup in his hand."

"But when is the big tri going to be test-sailing again?" we asked.

"I'm glad you asked," said the duck, "because the big news is that they'll be sailing shortly. If you're in San Diego, you won't be able to miss her. But at the speed she travels, you won't be able to see her for long — unless you're in one of those F-18s flying out of North Island."

Since the duck seemed to be such a know-it-all, we asked him who he was picking to win the next Cup. "Some chicks and I were discussing the America's Cup the other day, and figure BMW Oracle has their work cut out for them. I'm just a duck, but I figure this is going to be — because of the extreme speeds and risk of personal injury and boat destruction — the most NASCAR-like America's Cup ever."

- latitude / rs

Structure to support the Loads

Interesting photo of 'wired' support 'structure'

Well here is the portion of the lake trip:

...more HERE

Weird Daggerboards, Alinghi`s S-shaped Foils

They have a strange look:

http://www.sail-world.com/europe/Americas-Cup-Spycam---latest-images---Fitting-the-Boards/58725

But how do they work ?

This foil in the leeward hull can fulfill two tasks: horizontal/vertical lift or lateral lift.

In "normal" position the foil is a common bananafoil for generating vertical
lift like those of BMW Oracle. In this mode the upper part of the foil (that one
going in the other direction) is above the deck.

The secret ,or call it trick, is that the daggerboard-case is hinged to the hull`s bottom and goes NOT to deck level. Where the case is hinged ,one can see a rectangular area, similiar to those of canting keels.

Pushing now the foil further down , means that the daggerboard- foilcase angles it`s top towards windward, angling the bananafoil more vertical for generating more lateral lift.

The upper part of the foil never enters the daggerboard-case, you can see it on the red uphaul/downhaul rope on the pic. The upper part is guided by a slot in the deck.

A very clever invention I think.
Pogo (Germany)

Interview with Nigel Irens

Nigel Irens is one of the world's most renowned multihull designers, having been responsible for the design of several record breaking trimarans such as, Ellen MacArthur's B&Q-Castorama, Thomas Colville's Sodeb'O and Francis Joyon's solo Round the World record holder IDEC. More recently, Nigel was a consultant to the Alinghi design team.

He has been talking to BYM News editor, Marian Martin, about some features of the Deed of Gift protagonists, starting with the catamaran v trimaran differences.

Nigel Irens: Essentially both boats take the loads on a central structure. On the Oracle boat that structure is a hull that floats in the water when the vessel is at rest; Alinghi has chosen not to put the envelope of a hull around that structure, so clearly it mustn’t be allowed to touch the water, because that wouldn’t do a lot for the speed, because of the drag from the tips of the struts that come down. So that’s why the longitudinal vessel structure has to be held quite high in the air and the mast step, which is on it, is quite a bit higher than on the Oracle boat.

So how does this change things? There’s a fundamental difference, at this point between trimaran and catamaran configuration. Because Alinghi’s central structure is above the surface of the water, when the boat starts sailing it doesn’t have to heel very much in order for the windward hull to come out of the water, only a few degrees. Obviously, both boats are going to be sailed on one hull, most of the time, and as the Oracle centre hull is floating you have to heel that boat a lot further to get that hull out of the water. That is a point you can consider to be in favour of the choice made by Alinghi, because when the Oracle boat is on one hull, the windward hull is really quite high in the air and the higher it gets the faster moving air passes over it, so there really is quite a bit of aerodynamic drag there, which won’t be the case with Alinghi. So that’s one plus for Alinghi; on the other hand Oracle, has built a hull that has quite a lot of rocker on it, which is consistent with the needs of the structure because you want the beam to be fat in the middle and thin at the ends, and that is actually quite a good shape for tacking. As the boat comes through the tack, or gybe and the power comes off the main hull lands back in the water and, because it’s a rockered shape like that the main hull is quite good at turning. So, I anticipate that the Oracle boat would be quicker through a tack. Obviously, that’s a strategic position; the legs of the race are long and, on paper there’s not a lot of tacking to be done. On the other hand, if the two boats are very similar in speed, which I think is quite possible, then they could get into a tacking duel. If one boat thought they were faster at tacking than the other they would probably look for a tacking duel in order to exploit that advantage. On the other hand, there is a motor to power the Alinghi deck, so that may make up for a boat that is perhaps not as easy to tack as Oracle.

One aspect I find very interesting is that we are absolutely not privy to what the Oracle boat weighs and, if we find the boats are quite similar in weight, then I believe we will find they are quite similar in speed and that, contrary to first speculation some time ago, there might be much more of a race here than we thought. I was imagining that one boat would be faster than the other and that would be the end of it and rather boring from a racing point of view. Now, unless the Oracle boat has come out way overweight, which we don’t know, then it could be a lot closer than was first anticipated.

...more HERE

"Stored Power"

..courtesy of Scuttlebutt

Stored power… that is what all the fuss is about. Alinghi wants to use it, but is not yet ready to disclose the rules that would permit it. Too much time would give BOR the opportunity to create their own system. The fact is that Alinghi, because she is a catamaran, may have to use stored power to be competitive. Here are some comments on the subject from esteemed multihull sailor and designer Pete Melvin of Morrelli & Melvin:

“On the Alinghi cat, it appears that they are going with hydraulic winches and some hydraulic cylinders for other controls such as shrouds, forestays, and possibly mainsheet.

“I have done some quick weight calculations and think that if you added an internal combustion engine, hydraulic fluid reservoir and fluid, hydraulic pump, and hydraulic control system and piping but then eliminated winch pedestals and six 200 lb grinders, that you would save about 400 lb. A downside to this (stored power system) is that the weight of the grinders is movable, whereas the weight of the hydraulics is fixed. You can always add more bodies to increase righting moment.

“Having powered winches is more important on a cat with Alinghi's configuration because a lot of the sheets and control lines need to be lead to the windward side. You end up with some winch and hardware redundancy since this hardware needs to be located on both sides of the boat. Then there is the issue with space to place pedestals and grinders. With powered winches, you save the cockpit or deck space and associated structural weight that would be needed to support pedestals and grinders.

“Then of course there is the advantage that the engine does not get tired and could be sized to provide more power and faster trimming than humans.

“On a trimaran with a central cockpit, you do not have winch and hardware redundancies as on a catamaran, but the boat could be sailed more efficiently if you were able to trim the sails faster. Imagine if you were sailing your Tornado catamaran and could only move the mainsheet at the rate of six inches per minute. You would need to do a lot more steering to keep the boat in the groove and you would not be able to sail as aggressively in puffy conditions. Maneuvers would also take a lot longer!

Note the engine compartment off the rear crossbeam of Alinghi 5. Photo by Stefano Gattini/Alinghi.