Righting Moment (RM) is the force that tends to keep the boat upright. Heeling Moment (HM) is the force that tends to knock the boat over. Shifting the rig to weather will increase RM the same way shifting crew to weather does: The lever arm for the mass of the rig is increased. HM stays the same, because a rig of X height, having a center of effort Y feet above the deck, will ALWAYS have the same HM. Of course, as the weather hull flies, the HM increases faster than it does when the rig is centrally located, as it rises above the water (and the leeward hull) faster.

sail fast