@AdamCord, while I agree that there is a curve, and we are not completely planing, for practical purposes, we are. Since a water ski is only capable of as I said about 5lbs of lift as a displacement hull, my remaining (classified) mass must be lifted by planing, so while technically it is a combination, there is so little displacement going on, it can be ignored. I would argue that the reason that drag increases as we slow down is because in order to generate enough lift to keep the ski on the water, the angle of attack has to increase, which increases induced drag. On the other point, parasitic drag will increase as speed increases, but induced drag goes down as the angle of attack goes down. For a planing surface, the best L/D occurs IIRC just under 5 degrees, which we we rarely get close to on a slalom ski, so the bulk of the drag we feel is induced drag. I would say this is the the reason why it feels as though drag is decreasing while speed is increasing. It is because the faster we go, the further aft the centre of lift moves, which brings the tip down, which reduces induced drag.