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Old 10-08-2012, 09:09 AM
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ricki ricki is offline
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We experience some electrical phenomena while kitesurfing, just not apparently all such phenomena like inducing lightning strikes, to date anyway. Why is this?

Spectra and Dyneema kite lines are poor electrical conductors comprised of Ultra-high-molecular-weight polyethylene. If they are coated with salt and moisture the conductance may improve somewhat but how much? Looking at the example of most incidents involving one of our kites hitting high tension power lines, the lines conduct so poorly that they melt (and often the kite catches on fire). In some cases the kiter may suffer some flash burns but isn't electrocuted which you would expect with a reasonable conductor. I have read of kite related electrocutions when different line material was used say like nylon fishing line. Note to self, don't use nylon fishing line to fly kites! Folks have fired rockets into storm clouds trailing a copper filament and have nicely induced a linear bolt of lightning down the filament to the ground.

We know that kites and lines can have static discharges. These seem to occur both in conditions of immanent lightning strikes and in other potentially less threatening conditions. The static discharges appear to be caused by the Electret Effect and the line moving through aerosols.

A good question is, can our kite and line setups in kitesurfing attract stepped leaders from clouds and in turn lightning strikes? Falk apparently at less than seven feet in height did this on an open beach but I understand people are better conductors than kitesurfing system materials and a person's head may be pointier than a blunt, poorly conducting kite. The apparent lack of such an event seems to support the low probably of such a thing happening and yet there are the static discharges described above. It is important to note that untold numbers of people have been struck on level surface through time, no tall conductor necessary much less a kite. As such I would think a planning kiter might be struck regardless of having a kite up or not by virtue of having an induced positive charge and being the highest, pointy object in the vicinity. Thoughts?



Some background on induced charges and lightning.
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