You have seen them on the water, and maybe on the snow as well; riders racing along and boosting into the air at will, able to travel in any direct, and across any terrain while being pulled by the force of a giant kite. Kite sports have quickly evolved in the last ten years to become the newest and fastest growing “extreme” sport. So how does it all work? What are these riders doing to control the massive kites, and how is it possible that a kiter can stand on the beach or walk around while still flying a kite that moments before boosted him forty feet into the air? The secrets to controlling the kite all comes down to the design of the control bar, which is held in the riders hands and used to precisely adjust the tension in the lines attached to the kite.
Modern power kites like those used in kiteboarding today are built to fly on a four line platform, meaning there are two lines attached to the front of the kite one on either side of the center, and two lines attach to the back of the kite, one on each of the two wingtips. Simply speaking, with the proper amount of tension of all four lines the kite will fly steadily and maintain its course through the air, pulling at an amount based on how hard the wind is blowing. By adjusting the tension on one or more of the lines the rider can turn the kite to change its course, or alter the amount of wind the kite is catching to create more or less power, or pull, from the kite. In order to control a kite with the potential to lift a person 40+ feet in the air or propel them more than 50 miles per hour across water or land (the current speed record over water is 54 knots (or 62 mph), a kiteboarder needs to be doing a combination of both these types of adjustments at all times. For everything to work, the design of the control bar needs to be simple, and functional, and the solution turns out to be fairly simple.
The two back lines of the kite each attach to the outside ends of the kite control bar. By pulling one side of the bar in towards the riders body, and angling the other side of the bar toward the kite, the rider can increase the tension on one side of the kite. This causes the kite to rotate, or turn, around the wingtip being pulled on, changing the direction the kite is traveling. The rider will pull on one side of the bar or the other to adjust the direction the kite is flying in order to keep it from crashing, or to change direction, or to steer it upwards in order to jump.
The two front lines of the kite come together before reaching the bar, and attach to a single center line called the sheeting line, which runs through the middle of the control bar and ends in a plastic loop which attaches to a special harness worn around the riders waist. With the loop hooked to the harness, the control bar can be slid up and down the sheeting line, which has no effect on the tension of the front lines, but does loosen or tighten both outside lines simultaneously. By pulling the bar down the sheeting line and closer to his body a rider is increasing the tension on the back lines and therefore on the back of the kite, which makes the kite hold the wind more effectively and pull harder, or feel more “powerful”. When the rider slides the bar up the sheeting line and away from his body the back lines are loosened, reducing the tension on the back of the kite and allowing it to more easily spill the wind and “depower”, or create less pull.
This simple system in combination with modern kite design improvements has not only allowed professional kiteboarders to push the limits of the sports, also made the sport more accessible to everyday athletes and outdoor enthusiasts alike. Of course even with an understanding of how the equipment works, aspiring kiteboarders should definitely take a few lessons before attempting to fly the massive kites on their own.
Tips for tuning a four line kite control bar
- Check to ensure the two back lines (attached to the outside ends of the control bar) are the same length, and that the two front lines (attached to the sheeting line at the middle of the control bar) are as well. Front and back lines are usually but not necessarily the length as well.
- When first flying a kite you are unfamiliar with, attach the back lines to the ends of the leader lines on the kite (also know as pigtails), to allow for the most length possible in the back lines. When flying the kite with the control bar pulled all the way in towards your body, if there is still slack in the back lines and the kite is not catching the wind or is unresponsive to steering, then land the kite and tighten the back lines by attaching them closer to the kite on the kite leader lines (pigtails.)
- Back lines can be tightened in this way until there is a lot of tension on them with the bar pulled in, and the kite feels very powerful and sensitive to steering input. However, the back lines should not be so tight that when the bar is slid up the sheeting line and away from the riders body that the back lines are not loose and there is still tension on them, preventing the kite from spilling the wind and depowering.
- Too much tension on the back lines can result in the kite falling backwards out of the sky, or “stalling”. With the control bar pulled all the way, or nearly all the way, in for power, the kite should not “stall”. If it is then the back lines need to be lengthened a few inches.