Depends on the cat

Una-Rigged Cats can point higher.

But it is mainly (as usual) due to apparent wind and the interaction on the slot on Sloops

slow boat going to windward will be able to point higher as the aparent wind does not move so far forward
Fast boat will not point so high as the aparent wind has moved forward more

Simplest description I could comwe up with

To answer that is simple.

Because Cats sail faster than mono's

Go to the page : http://www.geocities.com/kustzeilen/sailvectors.html

and look at the first vector drawing that you encounter.

Than realize that a sailrig has a minimum angle of attack requirement. At smaller angles the saildrive reduces quickly AND / OR the sail will start to luff. Ergo a minimum angle of attack is required.

Now look at the two vector balances in the upper right corner of the vector drawing.

Assume that the most upper and most right one represents the catamaran and that the one just to the left and below that is the monohull.

It is clear that for both boats to sail on the same course (black dotted line) at their typcial speeds (cat > mono) that the angle of attack that the rig of the cat experiences is (significantly) smaller than that of the monohull. (Angle between the blue arrown and the black one laying along the travelled course)

Assume that both boats use the same rigs, a rig that has a minimal angle of attack of say 25 degrees, than is will be apparent that the mono must point higher at its slower speed than the catamaran to have its rig operate at the same minimal angle. If is points equally to the cat and the cat is at the minimal angle than the mono is sailing suboptimaly by sailing at an angle of attack that is larger than the optimal value.

So in simple terms with increasing boatspeeds a boat using the same rig at a constant wind must point lower to keep the apparent wind at the same optimal angle (Angle of attack).

Now is the winds increases than the boat can again point up a little when not changing its boatspeed. This is also a reason why mono's that have reached their max hull speed tend to point higher still.

Hope this make sense to you. If not than never ask question like these again, for they can only be answered when you learn to understand the Aerodynamics of sailing.

Wouter

You've got it right, Scooby.
And cats experience the more forward relative windspeed because they are going faster, faster in absolute boatspeed and faster in VMG. So what is pointing angle worth as a measure of windward boat performance? Not much. I find that older monohull sailors with white hair like to talk about windward pointing angle. Back when they were racing monohulls, that was big stuff. I guess it was important to point higher than the competition when you are all sailing to windward at hull speed limit. The only other variable left in the way of boat performance is pointing angle. This is "old timers" talk.
Bill

We have raced against monohulls quite a bit, and it is a myth that catamarans cannot point as well as monohulls. We can point at least as well. A Hobie Wave can point with Sunfish and Lasers. Any of the modern 18-20-foot catamarans can point with a Flying Scot. The difference is that we have to go a little slower than we normally do, in order to point as well as them.

It is not that we can't point as well as the monohulls -- it is that we don't want to. On a mixed starting line of monos and multis, we certainly can hold our own. In fact, one of the single biggest things catamarans can do to impress monohull sailors is to outpoint them at the start. For some reason this impresses them far more than our superior speed, because it busts the biggest misconception monohullers have about multihullers -- that all we can do is reach.

I see at least two definitions for "Pointing." First would be the measure of the boat's attitude in relation to the wind's direction. Second would be the boat's Velocity Made Good (VMG) in relation to the wind's direction.

In many situations where there is good wind, a well sailed cat, be it sloop rigged or uni-rigged, will outdo a mono's VMG to a weather mark even though she is being sailed at a lower angle of attack to the wind.

When the forward speeds of each boat are combined with their receptive sideways "slip," (a simple vector equation) the mono hull looses the upwind battle, even while she is sailing at a closer angle to the True Wind angle.

GARY

I'm not sure what you said, but I think I agree.

Mary,

The only cat that truly benefited by actual body kinetics upwind and downwind was (is) the Hobie 14. Body weight has a huge effect downwind and because of its length, able to surf very well. Ooching the loose rig forward also gets the boat down the face of a wave. You could also ooch the bows thru waves upwind if you could get in sync. By hiking very hard and/or trapezing, you can throw your weight back suddenly and pop the bows out of waves too. The current 17-18-20' boats get stuck in the troughs or just plow into the back of the forward wave so body movement is negated if sailed straight downwind.

Hope this helps,

Bob