Peggie Hall wrote:
Roger Long wrote:
"Richard Casady" wrote

Anyone here have any experience with roll stabilization tanks -
designing, building, tuning, etc. ?
Undoubtedly not.

Actually, Yes.

Roger, how does this differ from water ballasted sailboats (not that I
completely understand how THAT works either)?

Peggy,

Water ballast these days most commonly comes in two types:

Straight ballast (ala McGregor) most often used in small boats to
replace solid fixed ballast - like lead. This is a single tank in the
bottom of the boat that has to be filled nearly full to prevent the
effects that the free surface would cause.

Active ballast systems are used on many of the Vende Globe around the
world boats but not that others in a normal sailor's world. These have
two tanks and the high tank is dumped into the low tank just before
coming about (so it will be on the new high side). This makes for some
interesting times. Most have powered pumps to move the ballast water,
but these are much slower and use valuable power. Movable water
ballast is allowed under the current racing rules, but there are also
knockdown recovery rules that make active water ballast problematic.

I will leave this discussion here unless someone really wants to know a
great deal more.

Matt Colie