Recently there has been a lot of discussion on the net regarding this feature.
A discussion by Joe has also been published at…http://www.wingo.com/proa/articles/dave_culp_water_ballast.html

I found John Shuttleworth’s comments interesting but wonder weather he has missed the point a little.
Sure adding water for the sake of it will be slow. When flying a hull it will be fast.  He doesn’t discuss the extra power (kinetic energy?) that water ballast can add when approaching that transition zone between flying a hull
and having two hulls in the water. Increasing wind generally brings increasing wave height and the need for more brute power. Especially on a cruising boat which is probably short handed, the extra righting moment a little water ballast can offer allows one to push on, when reefing down would be the only alternative, hence average speeds remain higher than without it. For a cruiser this equates to faster.

Any thoughts?

Regards

I would think on a cruising proa that potentiall has fuel, fresh water or other consumables that aren’t directly over the keel, it would be handy even if just to keep the initial balance as these things are used up and then refilled.

The ability to remove weight/uneeded righting moment from the Ama for light airs also seems valuable to me.

water ballast in the main hull might be useful for more momentum in certain conditions as well as more “final” stability, assuming it’s low in the hull.

Lastly, I’ve seen it written somewhere that it’s easier to build light then add weight if/when needed than to build heavy and try to go the other way.  Makes sense to me.

Tom