What is Trajectory?

Trajectory is basically the path of motion that the boat is about to take, and it is essentially a combination of your angle, speed, usually (but not always), coupled with the effects of the current. In most ways it is more important where the boat is going next than where it is now. This all sounds really simple, and in many ways it is, however it is one of the more often neglected (or ignored) concepts of paddling in whitewater.

Every beginning kayaker has heard about the concepts of angles and speed for making peel-outs and ferries, but often even good intermediate level kayakers forget about them somewhat when in the middle of a big scary rapid. One way to simplify and visualize this is that as soon as you peel out and head down river you are establishing a trajectory; if you were to allow the boat to be spun straight downstream in the current that would be your trajectory. Downstream trajectory or momentum tends to come automatically, while our main concern is typically with establishing some amount of lateral momentum (trajectory).

Why is Trajectory so important?

Most kayakers have probably fallen victim to the trap of simply paddling harder to avoid an obstacle rather than first adjusting their angle. At the same time it is not really much more helpful to simply angle the boat one direction without "establishing" that angle with some amount of speed ("speed" is not always fast, it can simply mean having some paddling strokes to establish some movement). If you can imagine a move of having to cut behind one boulder to cut to the left side of another, you will have a move requiring a right to left trajectory; the greater the downstream movement that you have, the more lateral speed you will need. An extreme example of this, is if you have a move requiring you to move a great distance laterally within a very short distance downstream, you would probably need a ferry; the ferry would limit your downstream trajectory while allowing you to build up a lateral trajectory. Most of the times that you've found yourself having to really scramble to make a move, you could probably find fault in your use (or lack thereof) of trajectories.

Where you are pointed is NOT where you are going!

Probably THE best thing to remember, and how this makes the most difference in your overall paddling is that your boat does NOT change trajectory when you first change your angle; you've simply changed your angle, but your kayak is probably still moving in more or less the same direction that it was before the angle change. The most extreme example of the difference between simple angle and actual trajectory is to point your kayak upstream in strong current; although you have an upstream angle you will still have downstream trajectory, no matter how hard you paddle (if you give a slight ferry angle, and you will now have some degree of lateral trajectory). A common scenario where this is critical to understand is if you need to catch a smallish eddy, you will have an easier time catching it if you do not paddle too close to obstacle creating the eddy, too far upstream. Sneaking over to one side of the river way upstream will mean that you'll have to wait until your boat is passing the obstacle before you can change your angle (and THEN begin to develop your lateral trajectory). A good trajectory would be developed from somewhere closer to the middle of the river, and would allow you to be building momentum for your eddy much earlier. In the above example you can probably visualize that both strategies would cross paths right below the rock, THE key difference is in the angle of trajectory that they each have; one is moving downstream with little to no lateral momentum, while the other has set up an aggressive lateral trajectory and is probably only one stroke away from the top of the eddy!

So how do I develop "Positive Trajectories"?

More than anything you will need to spend some time reading your water and being able to assess the current speeds and angles, along with the affects of any features on your boat. Start out on some very simple tasks like catching a small to mid size eddy in current that is relatively straightforward; you will want to time it so that you begin to build your lateral trajectory soon enough that you can easily drive into the very top of the eddy, but not so soon that you "overdo it" and have to back off at the last second (as this would now be "negative trajectory"). Learning to time things correctly and read your water consistently will take time to develop, but keep at it, and be precise with your goals so that you can continue to hone your skills. Thinking ahead and keeping the concept of trajectory in mind will allow you to paddle more precisely and with greater fluidity and grace!

Look for more Trajectory technique tips in Complex Trajectories