• Kite Flying Faults 03 June 2018 | View comments

  • An In-depth Look at why Kites don't fly well  

    1 Flying Faults and possible action - or what to do if your kite won’t fly. The basic approach is from the point of view of a flier on the end of the line of a kite which is not in stable flight. Previous sections have included a certain amount of ‘theory’ to illuminate what is happening to the kite and therefore what can be done – although admittedly the theory is of more use in kite design. The discussion is largely in terms of a single spine kite with a 2 point bridle such as an Eddy or a Roller (see Drawings 3 and 4). It is easy enough to apply to a sparred kite with 2 or 3 bridles (e.g. Barndoor or a Box). But it doesn’t work with a soft kite with multiple bridles – no adjustment is possible in such cases, after checking that all the bridles are tight when the kite is inflated, except perhaps adding or varying the size of the tail/drogue. If you are experienced or skilled enough to handle a 10m gecko or a 2m Edo you don’t need help from this section to adjust it. 1.1 Immediate Instability The first problem is when the kite spins quickly as soon as it has been released or rises a short distance then turns and dives into the ground. I am assuming that either you are launching it from your hand or you have a helper 10m downwind who holds the nose upright and releases it as you give a slight jerk. I am also assuming that you know the second rule of kite flying. The first is DON’T LET GO. The second is SLACKEN THE LINE BEFORE A DIVING KITE HITS THE GROUND. This seems to run counter to the instinct of many new fliers but you will find • that a tight-line power dive into the ground can cause considerable damage; • that if you slacken the line, the kite will sometimes sort itself out or at least drift down nose up and • that if it does dive the impact will be very much less. Why slacken the line? Effectively, what you are attempting is to reduce the windspeed over the kite. If your line storage system won’t let you do that, then always have spare slack line laid out in a zig-zag on the ground in front of you when you launch. Alternatively you may have to run towards the kite or even, if appropriate, throw the line storage system towards the kite. If the kite shows this immediate instability, what can be done about it? Unless we are considering an untried design, there are two possible causes. Firstly, the kite has been incorrectly set up. So check it. The cause could run from spars in the wrong place through to a part of the bridle caught around the frame. The latter happens quite often with multibridle kites such as Barn Doors or Roks. One of my finer moments was attempting to launch my son’s Rok upside down – several times; at the start of an important Rok fight; and while disagreeing with his choice of language. Secondly, the wind is too turbulent or just too strong. While the former might be resolved by finding a better launch site, the latter might be coped with by adjusting the kite. On the field there are two things to explore. • on a 2-leg bridle move the ring or knot to shorten the top leg, moving the bridle point forward. By how much? Only experience will tell you, but for most kites 1 cm is a considerable shift • adding a tail or adding to the existing one. The limit to ‘additional tail’ is that the kite rises but can’t lift it. The problem is that until the tail is flying behind the kite its full effect will not be known. Quite often changing the tail requires you to change the bridle e.g. to compensate for the lower angle of attack brought about by the tail’s drag. 1.2 Faults in vertical elevation Consider the situation where the kite is flying so you are looking at the underside of the front but although ‘stable’ it is not flying perfectly i.e. a) it is at a lower angle than anticipated b) it is not quite straight into the wind c) it is not located straight downwind – often only spotted in comparison with other kites Examining each case: a) Of course some types of kite fly at lower angles than others. Assuming that it is stable and not sinking (in which case you might be pumping it i.e. pulling in a few metres of line causing it to rise, hoping that it would stay at its new elevation by willpower or increased windspeed), then the most likely cause of an unexpectedly low angle is that the wind is too strong. In this case, although the kite remains stable, the increased wind speed causes more drag than lift and the drag pulls the kite down-wind. The effect is increased where a bridling system which fixes an angle of attack means that the kite is at a higher angle of attack when low down – increasing the drag to lift relationship. Drawing 2 illustrates this. The solution is to move the bridle point forwards i.e. lower the angle of attack. Deltas are particularly prone to this and may become low angle hard pullers and in extreme cases break the spreader bar. Their bridle point is often fixed by being the low point of a keel. The article deltas does show a way round the problem. 

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