Abstract: An adjustable fluid foil. The fluid foil includes a foil support structure having one more spars. A first mechanism facilitates mounting the one or more spars to one or more supports. The one or more spars are independently controllable and form a frame that is covered with a deformable skin. A second mechanism provides a control signal, and a third mechanism selectively rotates the first mechanism based on the control signal, thereby reorienting the one or more spars and implementing desired changes in fluid foil characteristics. In a specific embodiment, the spars are telescoping spars that are responsive to control signals from the second mechanism, and the spars exhibit strategically different shapes to facilitate wing camber adjustments in response to reorientation of the one or more spars.