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 Post subject: Re: Kiteboarder Stuck By Lightning
PostPosted: Fri Oct 05, 2012 3:54 pm 
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I finally was able to get the archive radar site to work. Here is a copy of the radar image around the time of the accident, see below. The kiter was struck about 5 miles south southeast of the airport labeled "SGJ." You can see the two cells Eddie Toy was describing with the more serious of the two to the north and west of Vilano Beach. His description of the layout of the clouds looks pretty accurate.

So, the lightning bolt traveled several miles to strike the father and largely miss the son standing beside him. Considering the 30-30 Rule**, the distance wasn't that great.

They say the odds of being struck by lightning in Florida in a "normal" person's life are 3000 to 1. Now take that person, put them on flat beach or water surfaces, in proximity to squalls with some frequency, what are the odds now? For an even smaller, special group, have them kiting when their hair stands on end (a sign of an imminent lightning strike) , the control bar issues painful shocks and they can see static electricity arcs from the water when they jump. What do you think the odds might be for this last, special group? Think it over and about the weather conditions you will ride in, rider's choice.

More about lightning and precautions at:
http://www.preparemetrokc.org/know_the_risks/severestorms.asp

Again, we are far more at risk of being hurt or killed by excessive winds related to a squall than by lightning. That has been our experience since the sport started. Despite that, why risk getting struck and dealing with the aftermath, assuming there is one.


** Lightning 30/30 rule: If it takes less than 30 seconds to hear thunder after seeing the flash, lightning is near enough to pose a threat (about 6 miles away); after the storm ends, wait 30 minutes before resuming outdoor activities.


My friend Karen reminded me just how important knowing CPR can be in preserving life and health when things go badly. She has made sure that both she and her children know these simple critical procedures. We should copy her good example and should take training ourselves. CPR saved Falk's life and many others including some kiters over the years.


Strike Victim First Aid

1. Call 911 for medical help or send for help immediately

2. Assess the situation

3. Check for breathing and heartbeat

4. Administer CPR

5. Address other Lightning Injuries

More at: http://climbing.about.com/od/climberlig ... rstAid.htm

.


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Last edited by RickI on Fri Oct 05, 2012 6:52 pm, edited 1 time in total.
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 Post subject: Re: Kiteboarder Stuck By Lightning
PostPosted: Fri Oct 05, 2012 4:29 pm 
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I've been wondering about this for a while as it seems to me based on my GCSE physics that a kite hoisted 30m into the air over a surface where there are no other objects anything like that height around (ie the sea) is a pretty good target for lightning but I've never heard of any kitesurfer being struck by lightning...is lightning going to be attracted to a kite on the ocean?

Again with my infancy level knowledge of physics I would have thought yes but maybe someone with a more scientifically attuned mind can shed some light on the ins and outs.


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 Post subject: Re: Kiteboarder Stuck By Lightning
PostPosted: Fri Oct 05, 2012 7:43 pm 
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Ah not good news, I'm happy the man is alive though, not many people that survive such a hit. Must be terrible as a son to see your father falling to the ground after such a thing happening...

Couldn't help to think this though

Image


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 Post subject: Re: Kiteboarder Stuck By Lightning
PostPosted: Fri Oct 05, 2012 11:28 pm 
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edt wrote:
read that paper by cb moore from 2000 "Lightning Rod Improvement Studies" Lightning rods don't reduce lightning, but the shape is very important, sharp small shapes attract lightning, large round shapes don't.

edt,
CB Moore lived 1852-1936. at that time there was big argue between the different schools for decades about if lightning rods should have pointy ends or they should have spheres on the top of them.

as i see it now, many of the high voltage test facilities have the electrodes with the spheres on the end of them. but still, you can never be sure about kites in the air during electrical storms


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 Post subject: Re: Kiteboarder Stuck By Lightning
PostPosted: Sat Oct 06, 2012 4:17 am 
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eree wrote:
edt wrote:
read that paper by cb moore from 2000 "Lightning Rod Improvement Studies" Lightning rods don't reduce lightning, but the shape is very important, sharp small shapes attract lightning, large round shapes don't.

edt,
CB Moore lived 1852-1936. at that time there was big argue between the different schools for decades about if lightning rods should have pointy ends or they should have spheres on the top of them.

as i see it now, many of the high voltage test facilities have the electrodes with the spheres on the end of them. but still, you can never be sure about kites in the air during electrical storms


eree I have no idea what you are talking about.

I am talking about CB Moore one of the most famous atmospheric researchers of the past 50 years, he did some of that work with vonnegut (not the writer) about silver iodine cloud seeding, did some balloon microphone stuff to listen for the russians testing nukes, and invented the weather balloon.

He wrote a significant paper in 2000 about lightning rod shapes, which might explain why it's hard for lightning to hit a kite.

cb moore did the real research but I'm not gonna summarize it, just go read the paper, make sure you remember all your maths.


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 Post subject: Re: Kiteboarder Stuck By Lightning
PostPosted: Sat Oct 06, 2012 5:34 am 
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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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