I want to throw this out to the group: What do you think of the latest wave piercing hull designs: A2, Nacra, Capricorn.. I am guessing that the thoery is that the rig will pitch less with narrower bows because the bows will just go through the wave. But with the new nacra, it looks like they have just moved the volume back a few feet. Won't this just cause the boat to ride up over the wave and pitch anyway? I have been sailing a Nacra 6.0 which I think has a fantastic hull design.. The narrow hulls cause the boat to punch through waves, not ride over top, which to me is wave piercing. The hulls are about 12" wide at the front beam.
Comments?

The ability of the wave piercing hull to repell water with the rounded and narrow deck vs dig into water with a flat,wide deck is the factor, along with bouancy distribution. Simplistic in my mind, minimizes the propensity to pitch.
(?)Are my assumptions close?

Timbo: Stuffing the bows underwater is not such a big deal. The big deal is do they come out? I think that the older design sheds water pretty well. I sail a Tiger and I am always concerned when the water is on the deck. With the deck being so flat it likes to stay underwater longer than the older design of the Nacra F18. I have stuffed it to the crossbar downwind and saved it but that is do mostly to the incredible crew that I have. She sticks to the boat like glue and has never fallen so far forward as to pull the boat over (knock on wood).

The new Nacra is designed to take advantage of the fact that you may sail in swells. If it goes down it will shed water better than even the older F18. As far as it getting there in the first place the bow seems to stay higher out of the water without too much tendency to submarine. The boat steers very easily downwind. It kind of sits up and goes were you point it instantly. I think it may be easy to over control it, steer too much. As a matter of fact, very similar to the way a Hobie Fox steers downwind.

Countdown to Wouter jumping in with both feet . . .

5 . . 4 . . 3 . . . 2 . .

The ideas behind the A2 and the new Nacra F18 are not necessarily to punch through every wave. The idea is to get the boat into a different rhythm where instead of leaping over every wave, it alternates between pitching over a wave and pushing through one. The result is that the rig pitches less and you're still not trying to plow the bow deep under water constantly. Moving the bouyancy around accomplishes this task.

Having briefly sailed an A2, I can say that I've never been on a boat that was more silky and silent through the water. It will be interesting to see how the same concept applies to a two person boat that carries a lot more weight.

Yea hope so..
Might make the thread a little more interesting...

Hey flying cat if you don't have anything positive to say they why say anything?

I can offer my observations since I have owned and sailed a P-19, Tornado, Auscat Mk. IV, Auscat Mk. V, and now currently an A2.

The biggest advantage I see to the "wave piercer" A-class designs is less pitching upwind in chop and better handling (they turn easier and quicker). My Auscat Mk. IV was every bit as "smooth" through the water in flat water as any of the newer A-class designs. In flat water, I think it tacked on par with my Mk. V. In chop, you noticed a definite improvement with the Mk. V in keeping the boat quiet sailing upwind (i.e. less pitching). The design of the bows and the volume distribution allows the boat to sail through chop easier. The swept back bow of the Auscat and Egner Flyers enhances that attribute.

The A2 improves upon the Flyer design IMO by distributing more hull volume further aft and has a bit more hull rocker fore and aft. That coupled with very high aspect daggerboards and large rudders results in the quickest turning A-cat ever. Downwind in wild thing mode, it is amazing how you can steer this boat up, down, and around waves. I have never sailed another catamaran like it. You find that you work the boat harder (the first catamaran where I have actually pumped the main downwind) and it rewards you with better VMG.

As far as pitchpoling downwind, from my perspective I've never felt the wave piercers were more or less susceptible than my P-19, Tornado, or Auscat Mk. IV. They all can and will and you have to learn the traits of each boat to keep your transoms in the water. That said, I think the improved handling the wave piercers offer can let you push the boat harder and not get "spanked"! In regards to the A2, it is advantageous to move aft sooner than other A-Class boats and most A2 owners are sailing in light and heavy air with more aft mast rake. That tends to keep the bows up more while the further aft volume distribution and rocker keeps the transoms from squatting down. It is really a fun boat in 12-18 knots to sail in waves downwind.

Bob Hodges
A-Class USA 230

Hey pitchpoledave,
I thought I was being positive.
I enjoy your posts too!
Have a good one.