All modern power kites, not only use the wind strength to generate power, they also use the Bernoulli’s principle. This in simple terms means that, because the upper surface of a kite is longer than its lower surface the air must pass more quickly over it, which reduces the pressure above this surface creating lift. This is exactly how an aeroplanes wing works. The lift, combined with the wind, speed means loads more power. And more power means more fun.
Kites are designed to operate in a given wind range in relation to body weight and most manufacturers state their recommendations in the instruction manual. This means, if you want to fly in all wind conditions, you will need more than one kite and a collection of kites is called a quiver. Modern kites fall into two main categories, inflatables and foils, with some cross over highbred kites that bridge the gap between the two.
Foil kites use the power of the wind to inflate and maintain the kite’s aerodynamic shape, in a similar way to a modern parachute. The kite or wing has two surfaces, an upper and lower, and the shape is defined by the cord.(see figure 1) The leading edge has a series of vents in the front. The vents allow the air to pass into the kite. The materials used allow air to slowly release which maintains pressure in the wing and in turn keeps its shape.
Foils have two different control systems - bars and handles. Many kites can be controlled with either system and the choice is down to personal preference. However some designs mean that only a bar can effectively be used.
2 line kites
use two lines one held in each hand for control of the kite, just like traditional stunt kites. Pulling one of the lines changes the shape of the kite and this change turns the kite to the left or right. The simplicity of this style of kite makes them an ideal introduction to the world of power kiting. Ozone is the only manufacturer at the moment to offer a three line trainer, which adds extra safety to learning.
4 line kites
kites work in the same way as 2 line kites but they have additional lines connected to the trailing edge. These lines, often called brake lines, allow a greater change in the shape of the kite and give the pilot greater control. These kites are usually flown on 4 line handles. A bar will also work although you lose some of the advantages of a four line system.
The kites at the moment, are always controlled on a bar, but still have 4 lines. The lines in this instance not only control the shape but also the angle of attack. The angle of attack (see fig) directly translates into the amount of power the kite generates. The pilots can usually affect the angle or power of the kite in two ways:-
- pull the bar towards themselves to increase the power and away to decrease it.
- adjust the trim strap to change the overall power by pulling it towards themselves (sheeting in) to decrease the angle or letting it out(sheeting out) to increase it.
To fly these kite you will need a harness.
The range of foils in today’s market is massive and they cater to every aspect of kiting from static to surfing. It’s down to you to choose.
Inflatable Kites Designed primarily for water use, Inflatables have bladders that form the leading edge and the struts. These are pumped up using a hand pump, with enough air pressure to keep the kite rigid and create the aerodynamic shape while flying. Having an inflatable leading edge, means that the kite will float on the water indefinitely and, with the right technique, can be re-launched after a crash. These kites use a bar system like depowerable foils, with the same trim and bar systems to change the power of the kite. Inflatables fall into two categories – C-kites and bows
These classic c shaped kites are considered to be the original true kite surfing kites. They give excellent performance and a very direct feeling to flying. They come with four main flying lines and some have a fifth line for added safety. These kites can have a more limited wind range and so, often, a larger quiver of kites is needed to get out in all conditions.
Hybrid/ Flat/ SLE/ Bow Kites
have a much flatter shape, similar to a foil. Due to this shape
(Suported Leading Edge) changes in the angle of attack can effectively depower the kite completely. These kites are ideal for learners. They are forgiving and have excellent safety systems. They also work exceptionally well unhooked for today’s technical freestyle moves. More and more top riders are swapping their c’s for sle’s
Although not designed for land use, some riders prefer their performance characteristics. The bladders cannot cope with hard landings on the land and will burst if the kite is repeatedly flown into the ground. Replacement is possible but can be costly and may have to be undertaken by a professional repair company. It is for this reason we recommend that only experienced riders buy an inflatable kite for land.