Both the Fox and FX-One have reverse bows:
The shape of the bow is partially the result of it being wider at the bottom than at the top. This "upside-down" bow shape has its the widest beam at waterline level. In light conditions the boat is wave piercing, whereas in stronger winds the crew places their weight further backwards and the boat starts to plane. In contrast to boats with traditional V-shaped cross sections, the boat stabilizes itself at higher speed due to dynamic lift, reducing pitching. Less pitching leads to a more regular airflow around the rig – especially in the upper part – and increases the efficiency of the rig.