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arXiv · 2610.23444

Hydrodynamics and propulsive efficiency of stern-sculling propulsion

Gildas Roudaut·Benoit Augier·Marc Rabaud
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Abstract

Stern-sculling is a traditional form of human-powered boat propulsion in which a single oar is oscillated laterally at the stern. In this study, we investigate this propulsion technique from a hydrodynamic perspective by continuously measuring the oar kinematics, the boat motion, and the forces acting on the oar across a broad range of boat speeds. During the lateral strokes, lift serves as the main propulsive force, whereas during the backward strokes, propulsion is primarily associated with added-mass effects. These measurements allow us to determine the propulsive efficiency as a function of boat speed. The efficiency peaks at approximately 65\% at an intermediate speed and then decreases progressively to approximately 25\% at higher speeds. These results provide insight into the hydrodynamic mechanisms governing this traditional mode of propulsion and highlight the effectiveness of stern-sculling at moderate speeds.

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Gildas Roudaut, Benoit Augier, Marc Rabaud. 2026-10-16. Hydrodynamics and propulsive efficiency of stern-sculling propulsion. https://arxiv.org/abs/2610.23444

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