Three different kite designs of varying aspect ratio and conicity are tested. The hydrodynamical coefficient are established using a novel test method that includes suspending the kite horizontally in eight retaining wires and measure the tension in each. Results show that the maximum coefficient of lift and the matching angle of attack is quite dependent on aspect ratio. Conicity seems not to affect the maximum lift coefficient. Drag seems to be relatively unaffected by changes in aspect ratio. The work has resulted in a very useful methodology for testing flexible kites and the outhors suggests that future work be carried out in order to establish the optimal kite design.