Wind more than sea state is the principal problem kayakers face at sea. Beam (side) winds and gusting winds are especially troublesome. In practice, European feathered paddles describe an arc through the air with each stroke. The blade rotates in the air during this arc to present a flat side at the apex of the stroke to any beam wind. This results in maximum pressure on the blade and leverage on the paddle from the beam wind as the blade is high and also at an acute angle, causing wind pressure to induce lifting forces. Consequently the kayaker using a European style paddle has to have a firm grip on the upside part of the shaft and have tensed arm muscles to control the blade in the air.
Narrow blade and European flat blade. The centre of force of the wind on the wide, flat blade is farther from the paddler's hand grip creating more leverage.
In practice these wind effects start to become a problem for even experienced kayakers at Beaufort Force 5. At stronger wind speeds it can be a real fight in beam winds to maintain control of the blade in the air, especially on the upwind side. In contrast, the Inuit narrow blades are unfeathered (both parallel to each other) so that the blade in the air presents an edge to any beam wind. In practice these paddles are unaffected by strong beam winds. They are also not as affected by head winds as might be supposed because the centre of effort of the wind is several tens of centimetres closer to the paddler’s grip and there is less leverage compared to a European blade at the end of a shaft.
The absence of any significant wind effect on the unfeathered narrow blade in the air, is one of the principal advantages of Greenland style blades.
- from: Sea Blades: Fashion or Function? (2001) © Peter Lamont, Isle of Luing, Scotland.