-- In harryproa@yahoogroups.com.au, "Peter Southwood" <peter.southwood@...> wrote:
>
> Why would a microburst move the apparent wind forward?
>
> Peter

I believe because a multihull in a blow - instead of healing over under the increased sail pressure like a mono - very quickly accelerates forward which moves the apparent wind forward. That in turn causes a wind vane to make the boat bear away as the vane tries to keep the preset angle to the wind at all costs and as rapidly as possible. If it bears down far enough chances are that it will stuff the bow/bows into the next wave. Under certain rough conditions a dampening element is certainly needed.

Same thing happens when the boat is accelerated by a following wave and starts to surf. Monos like Mini Transats or Figaro 2 have that very much problem travelling under spi down large waves which is why they have accelerometers with fancy algorithms build into their steering compass. A nice video demonstrating the problems/challenges for an autopilot are demonstrated here:
http://www.youtube.com/watch?v=z_ExqQ80T5g

But as Rob pointed out already those pilots are very expensive (USD 10.000) and they tend to break or leak hydraulic fluids or whatever.

Besides -I look forward to see how a proa would do in such wind and wave settings..

Heinrich