Controlled Stability System

The original Sport incorporated a new innovation in its design which enables the designer to control the level of stability and instability of the wing. Without argument, a school glider needs to be very stable. Not only does the school glider need to resist collapses, but it also should make the pilot feel secure, and not be too sensitive to weight shift input through the harness.

On the other hand, a high performance glider needs to sensitive to the weight shift inputs from the pilot. An intermediate glider like the Sport lays between these two extremes, and so the designer needs to create a glider which reacts to weight shift but must not feel so insensitive that the pilot cannot lean and cause some weight transfer. This new design is what we call the 'Controlled Stability System' and allows us to produce a glider with a carefully designed amount of weight shift and stability.

World Champion Pilot and Airwave Designer, Bruce Goldsmith, explains:

There are many forms of stability but one important form is the way the two surfaces of the glider are linked together. This movement between the two halves of the glider is linked directly to the pilot though the risers, and then down to the seat plate of the harness. Because the pilot is sitting in the seat of the harness, he/she feels unstable if there is a lot of movement between the two wings.
Limiting this movement makes the glider feel much more stable, but there is one penalty: you lose the ability to weight shift. This solution is therefore ideal for a glider like the Gecko, a LTF 1 glider where stability is of prime importance, and this has been common knowledge in the design of paragliders for many years. The same effect can also be achieved by the lines of the glider meeting at he center, but again this has the same problem of producing a rigid glider that does not respond to weight shift.

So, if you want a glider with more stability you can use cross bracing in the sail or in the lines, and if you want a glider which weight shifts well, then you should use a standard cell in the centre of the wing. How much instability you feel from the centre cell depends on the size of this cell. On a Magic this cell has a width of 182mm on the Medium. But here comes the problem, an intermediate glider has wider cells than the Magic, so if you used the normal cell width for the centre cell you would have a glider that feels more unstable than the high performance glider.

The solution is astoundingly simple - just use a narrower cell in the centre of the glider. The degree of stability is controlled by the width of the center cell. Choosing the correct width gives the designer the ability to precisely chose the level of stability and weight shift he/she needs.

Sketch of the Magic:
In a competition glider, weight shift is very important. To have a glider that weight shifts well, the centre cell is therefore left without bracing, so that the individual wings (top and bottom) can move independently and the central cell can move like a parallelogram. This is helps to give the Magic its amazing handling.



Sketch of the Sport:
The Sport is the first production glider to incorporate this new technology. I would not be surprised if one day all gliders will be made like this!