AC Thoughts (Big Boats)

It seems to me, that in general, the design of the last few America’s Cup fleet, has stayed relatively the same. Nothing extraordinarily different from the years previous. Wouldn’t it seem that we (around the bouy big boat sailors) would have seen more of a trickle down effect by now in the hull designs. It seems to me that a standard production bouy racer is almost at the other end of the spectrum from an AC boat, also a bouy racer. Not that I think AC boats are nicer looking than say a, Melges 32, but it just seems odd to me. Any opinions and/or enlightenment is greatly appreciated.

I would think that AC. hull design is a product of that class design rule. No doubt faster hulls could be designed to an open rule. Rig and sail design innovations have no doubt influenced general yacht design.(even models)
Peter

i would also not venture so far as to say they have not changed… the general form has stayed to same to the eye, but i think that you would find if you were on the design teams of any of the components, from the 100 million dollar mast program to the sails, to the keel, to the shape of the bulb, the boats are very different. that said, all rules form a type… the 12 meters had a certain look, the new AC’s have a look, so i agree that the boats seem to follow form, each is a singular boat, with visable differences to the people on the inside…:confused:

The ACC rule has been around since 92…so overtime you see the boats get closer in looks and performance.This happens to all rating rules.They eventually type form.

Also the eventual "type"that any rule produces is very specific to that particular rule.features of the boats are largely driven by getting the best from the rule.obviously a diferent rule will produce boats with different features.

Some of the features of the 2003 boats have been further explored in the latest boats.Peole who follow the development of these boats see quite a bit of difference since 2003.
A couple of thigs are obviously different this time around. the hull volumes are spread further into the ends than the last go round…and the roaches of both the mainsail and genoas has reached new levels…More astute cup watchers will see other differences.
Obviously a 2003 boats would not stand a chance out there this time around.

The IACC rule is an interesting beast. The 2003 rule (I haven’t gotten around to reading the latest one) is a whopping 55 pages long. The basis is the old International rule which governed the 12 meters. Certain aspects of this rule drive designers in the direction of slab-sided hulls, which is why telephoto shots of IACC boats from dead astern make it look like a bunch of people have gone to sea in a horse trough.

The rule has been around so long, and tweaked so much, that it now exhibits the characteristic called “type forming” in that all designs sit around a particular spot in the tradeoff space (sail area vs. displacement vs. waterline length) and the differences are in the details. Whether by accident or design, this satisfies the organizer’s desire of having close and exciting match races and still have enough design variation to give the the techies (like me) something to study.

Cheers,

Earl

Earl and everyone,
Thank you for your responses. Now the next question is, how fast is an AC boat compared to other round the bouy racers? I realize this is a big window of other boats, but are AC boats that fast. Or are they just fast when they are confined to the rule?

That’s a question that has to be answered with a question :slight_smile: Fast where? All AC boats clear back to the J’s and before, were optimized for the predicted wind and sea state of the venue.

Cheers,

Earl

There is an article on Sailing Anarchy comparing a ACC with a V70.

Another interesting article, this time on the J’s, at Sparkman and Stephens:

http://www.sparkmanstephens.com/news/JClass_Racers.html

Cheers,

Earl