Optimal design, "water-wing" - single oar propulsion Good evening, and hello to you all. As you can see I'm new here, so please go easy on me. A while ago I got to learn about the single oar propulsion system used in southeast Asia. The way I see it this is a principle with loads of potential, far superior to any alternative man-powered propulsion systems. Conventional rowing is of course faster, but it's restricted to small boats and short distances. For those who are not familiar with the principle it works like a wing. The oar moves from side to side astern of the ship, generating lift to propel it. The person operating it only has to overcome the drag of the water. I want to make an oar like this, but before I start designing it I need to narrow down the uncertainties, understand some basics - and hopefully getting some hints & help. First and foremost I want to focus on the "wing", both because it's the by far most important part and because it's the most physic-related problem. My suggestions and questions so far: The oar will enter the water with about 45 degrees. The steeper the angle, the less thrust will be wasted. However, if the angle is too steep, operating the oar will be very hard. To bend the shaft will be necessary, both to counter this effect and to easily twist it at the end of each turn. (This bend will be discussed later in the process). The profile of the oar will be like the wing of a plane, but it has to be symmetrical. The reason for this is that both ends will be the leading end every second stroke. This one of my most important questions: Does anyone have a good idea as to what a symmetrical waterwing should look like? I am thinking about a mirrored basic wing profile, but especially the ratio between thickness and width is puzzling me. Also angle of attack, length and speed are related issues here. Then there is the question about varying the profile over the length. Especially if the wing is long, the speed of the end will be much higher than the speed at the waterlevel. To me it seems like a must to take this fact into account. Finally, is there any easy way to calculate the lift and drag of a wing trough water? Any free software available? A familyfriend is in a line of work that enables him to construct this wing for me if I actually design something useful, in this case it will have to be drawn in ProE or something. I hope I can get some help here, this is getting much more technical than I had in mind..