7. The sailing vessel as claimed in
claim 1, wherein the keel extends from a rotational housing that extends axially around said longitudinal axis; wherein the rotational housing is hollow and a superior portion of the rotational housing is within the hull of the sailing vessel, a part of the rotational housing which extends below the hull when the keel is in a neutral position being generally cylindrical,
wherein an upper part of the rotational housing is of a generally truncated conical shape, the rotational housing having opposing lateral sides and each of said lateral sides having an upper portion that is profiled from fore to aft with an overall conical shape; the conical upper portion of each of the lateral sides being configured to act as a foil; the rotational housing being configured such that windward canting of the keel causes the windward lateral side of the rotational housing to be retracted into the hull and the leeward lateral side of the rotational housing to be deployed from the hull by the canting rotation, such that the profiled conical upper portion of the leeward lateral side of the rotational housing is in the water and acts as a foil promoting lateral resistance in the water and generating lateral lift which opposes leeward drift of the sailing vessel.