It's been long controversial in the rowing community if and how much lift occurs in the sculling stroke. The data has been sparse. We can consider several factors: a) consistency of force production with lift versus drag force In the drag force case, the blade must be moving backwards [relative to still water] in order to generate the thrust. F = A*Cd*1/2 *density*v^2. b) production of an isolated single major vortex during the beginning of the stroke. Aerodynamic [hydrodynamic] theory requires that a single vortex be produced upon the acceleration of an air foil. The paired vortex remains circulating on the foil until the foil is stopped. You may investigate this further in the lift.html web page Force and power basics. The measured drag force for a racing 1X at racing speed is about 15 lb. In MKS this translates to 68 Newtons and the speed is about 4.8m/sec. The power requirement is P = F*v = 68*4.8 = 326 watts. For a sculler with drive/recovery ratio of 1:2, the average force during the drive must be 204 N (45lb). The force perceived by the sculler will be greater than this because the sculler and the oarlocks and oars are part of an accelerated system. [a 1 lb object feels heavier when you are being accelerated upwards. At 1 g upward acceleration, the object will have an apparent weight of 2 lb.] A scull will have an acceleration of about 1 g and the force will not be applied evenly during the stroke. The peak forces measured in the shell may be about 4 times more than the average force as seen by the water. The peak forces as measured in the shell will be about 800 N or 180 lb.
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