Water ballast more tender
My understanding is that a water ballasted hull is more tender in the normal operating range (up to 15 to 20 degrees of heel) and similar to a shoal draft hull at higher angles of heel.A shoal draft keel is designed to ballast like the full depth keel. The difference is that the shoal draft keel is less efficient, providing less lift and more drag while close hauled. The most important effect is that a shoal draft keel won't make good a course as close tot he wind as the full keel.DavidLady Lillie