However, just tipping the ski on edge will not form a very deep arc on conventional skis. Simply tipping the ski on edge and riding the edge will result in a very large radius turn, and cause the skier to pick up a lot of speed, more than is comfortable for most beginning and intermediate skiers. In order to make shorter turns, and thus control speed better on conventional skis, the skier must pressure the ski, which causes it to bend. This bending of the ski causes the edge to form a deeper arc in the snow, causing a shorter radius turn. In addition, steering the feet throughout the radius of the turn can shorten the radius of the turn and aid in speed control.
Parabolic skis have a much deeper sidecut than conventional skis.
They are pretty easy to spot on the mountain, due to the large tip and tail, and the hourglass type shape. In fact, many refer to these skis as hourglass skis. As a result of the deeper sidecut, much less pressure and foot steering is needed to make a pure carved turn. In fact, on easier terrain, all you need to do is tip these skis on their edges, and they turn pretty quickly. It is highly recommend getting yourself a demo pair of parabolic skis, even if you are not thinking of buying skis, just to see what they are like.