Let us first look at how a dart flies through the air. The path it travels along is known as a parabolic curve. The same path is followed by anything that is thrown within initial degree of steepness such as the throwing of javelin or the firing of a bullet from a rifle.


The size of the curve can vary in height. The two factors that affect this property are the initial angle the dart is thrown at, and how powerful the dart is thrown. As you are a constant height relative to the dartboard, it can be assumed that the curve height is dependent solely on the latter property. A decent throwing technique must guide the dart exactly along this parabolic curve when it is accelerated and It must also guarantee that the dart will continue along this curve if the dartboard was not there to stop it's flight.

So, how do we move the dart in order to keep it in the correct position? Well, to work this out we have to look at the mechanics of the throwing arm. It can be described as a 'machine' of 3 levers attached to each other by 2 joints or 'hinges', and with 1 joint attaching it to a fixed point.


Looking at the above image, the 2 attaching joints represent the elbow and wrist, the fixing joint is the shoulder, while the 3 levers are the upper arm, the forearm and the hand.

Those of you who had the misfortune of being tortured by mechanics in school will remember that this is a very neat arrangement. It can theoretically draw every possible curve within its range when the levers are moved properly, and although the human arm is slightly less moveable, the parabolic curve is still an easy exercise.