Jeff Cooper of H2Outfiffers shared with me a simple analogy to explain weather cocking. A common definition of weather cocking is that “a boat moving forward points into strong winds”. I have heard some people say that wind pulls the front of a kayak. I have never felt wind pull me. Then I have heard that wind pushes the back of the kayak, and a lower volume stern will decrease its surface area. Wind pushing the back of a boat is an interesting idea when the paddler is of average size. On a sailboat, wind pushes the sail, and a person in a kayak is more apt to catch the wind than their stern due to their increased surface area. Unless the surface area of the stern is greater than the paddler’s torso. All of these aforementioned ideas can make a person’s head spin.
Thankfully, there is the picture of an icebreaker that can make weather cocking easily understood.
The front of an icebreaker is static. Behind the ship is a smooth waterway. The back of the boat glides free and this is where boaters steer their craft. Forward motion of all sea going vessels produces this effect. Wind always has the most push against the tallest and most exposed surface. The body is what wind pushes. The stern of the kayak slips downwind due to the push on the paddler. The person moving the kayak forward is the cause that produces the effect of the back of the kayak to slip downwind.
Another way to think of weather cocking is to have you and a friend work together to illustrate an experiment. Hold your arm out strait. Have a friend gently push your arm at the elbow moving it three inches. Then hold your arm out strait again. Have the same friend gently push your arm at the wrist moving it three inches. When your arm is pushed at the elbow (the center of the arm) you wrist moves father than it did when pushed at the elbow. The same thing happens in a kayak.
To compensate for this natural action use a: rudder, skeg, stern draw, combined with edging (j lean) and have short forward stroke.
There are the other variables that can increase the appearance of weather cocking: current, flowing seas, hull design, paddler’s weight, how gear is balanced within the hull, the length of the paddler’s paddle, and the length of the paddler’s forward stroke. All of these variables can increase the appearance of weather cocking. And we will explore each variable in future posts. When you find the perfect combination you have a better chance of paddling a sea kayak with no weathercocking effects in most sea conditions.
Nice post Jeff. Having recently lost a rudder in the middle of a stormy ocean swell I experienced first hand how nasty weather cocking can be, although this was caused more by wave action than wind. Either way it certainly made me work pretty hard on that forward stroke to keep me going in roughly the right direction!
Sean, you make a great point about wave action. In a future post I hope to distill how rocker and chines influence the forward motion of a kayak.
And you also make a good point about gear failure, and the importance of knowing corrective paddling strokes.
I like your analogy of the wind pushing the paddler; however, I think your explanation should include a couple of other points with regard to water pressure and/or lack of pressure on the surface of the kayak. When a paddler is moving forward the kayak is displacing water with each stroke. As a result the bow is being forced into the water that in front of the boat. In theory, equal pressure is applied to both sides of the bow. This equality of water pressure tends to “hold” the bow in place and also creates a “void” or low pressure trough for the remainder of the kayak, especially for the stern. With the absence of pressure the stern is freer to move. So as a result (as you have already pointed out), the paddler being aft of the bow, the wind pushing on the paddler, and the stern having the least amount of pressure applied to it, the stern moves downwind.
Jeff…..keep up the good work…