Lightning Safety

I'm just guessing, but I wouldn't think it'd be much different than anything else on the road. You have less metal structure to carry current, but you also have less metal structure to act as an attraction to current. Maybe you'd do worse if you got struck, but are far less likely to be struck from the lack of metal mass around you. You're still sitting behind a metal motor and inbetween metal suspension components, you're just missing the shell. It would be interesting to know whether large areas of sheet metal are what attracts lightning or if it's the dense smaller masses underneath it that do the trick. Maybe it's even the number of "ugly bags of mostly water"* that are the biggest problem. If that's the case, you're much better off in a plastic sports car.

Cheers, - Jeff G

• from Star Trek, an alien's reference to humans

Dan Bergmen wrote:

Lightning is attracted to sharp metallic objects. If you've ever seen a lightning rod, you'll notice that they're just spikes that stick up off the top of a building. You'll also notice a thick gauge wire that runs off the lightning rod that should be routed to earth ground.

If you're in a field of only you and your corvette, I'd be worried. Otherwise, I wouldn't really worry much. The corvette isn't very pointy and it's insulated from the ground via the tires. Because the corvette doesn't offer a better path to ground, as far as lightning is concerned, it doesn't even see you there. If you were to get struck, it would seem as if the lightning would go for the engine or the frame, rather than you.

-Bruce

Approximately 9/4/03 17:08, Bruce Chang uttered for posterity:

Some lightning rods have big round balls on the end, not a sharp point. The difference is merely fashion as far as effectivity is concerned. The real purpose of that lightning rod and the grounding cable is to *avoid* a lightning stroke by allowing any built up charges to dissipate more or less harmlessly... And if there is a stroke, hopefully it will only be a small one.

For smaller high voltage fields, there is some benefit to sharp points in bleeding off charge. For fields the size and strength of the earth and cumulonimbus, you'd need a sharp point the size of the Empire State Building.

Worse, if your lightning rod gets whammed a good one, it will usually vaporise any and all of the connection points from the ground cable [wire is worthless] in the process. Our old meteorology towers had 1 inch by 2 inch phosphor bronze bus bars for lightning bleed... and we had to inspect them after every thunderstorm, usually replacing one or more sections if the tower was hit.

If the Corvette is moving, it isn't at as much risk if standing still. All else being equal [and with lightning it never is] the lightning will strike the highest point it can find *nearest* to the highest charge at the bottom of the cloud. The little qualifier about nearest charge is why lightning isn't that predictable... the charge in a cloud is not uniform by any means and neither is the reflected reverse charge this sets up in the ground under the cloud.

The distribution of charge in any given cloud is so uneven that cloud to cloud discharges are orders of magnitude more common than cloud to ground.

Depends on the stroke size and number of same. A lightning stroke is actually several separate discharges, including some which go in the reverse direction. A really large single discharge will cause enough corona that it is extremely uncomfortable and dangerous to be within several meters. If there is a smaller initial stroke, it builds a plasma channel that successive strokes *tend* to follow.

Pointy has little or nothing to do with it. The metal in the car won't really attact lightning since there is no way for the charge in the cloud to build up a reflective charge in the Corvette.

If it just happens to be on a local high point and the stroke(s) pass through it, the driver may, or may not, feel much.

What the Corvette owner wants to do is use the Corvette for its intended purpose. Thunderclouds are fairly slow moving and it takes a while to build up the ground charge under one... long enough to play hockey player and get the puck out of there.

That is why I never carry a pocket knife in a lightning storm ;)

Lightning will go for the tallest object in the field gradient. Human body is full of electrolytes. After punching through a mile or more of air I fail to see how a bit of carbon loaded rubber will impede it.

Go for the low ground. Under an overpass is good to. Not in a tornado, no matter what they show on real TV.

Thanks, Lon, for your wise input, I really appreciate it.

Thunderstorms are so rare in these parts that everybody usually freaks out, the local media goes nuts and there is little knowledge disseminated and virtually no credible advice shared.

Which is exactly what I did - I lit the afterburners...

Dan

Approximately 9/5/03 09:25, Dan Bergmen uttered for posterity:

If you are ever near a thunderstorm and experience *either* of these two sensations, either hit the deck as quickly as you can, or bend over as far as you can and reach up and kiss your *ss goodbye.

o A sensation of buzzing, as if a huge bunch of bees on amphetamines was in the area or worse, inside your head.

o A sour, metallic taste in your mouth. May be accompanied by a feeling much like a big spike being driven up your nose.

Both indicate that you are in a very high voltage local field, well above the threshhold needed for a strike. If the metallic taste all of a sudden changes to metallic plus the bees, the air in the area has already started to conduct for the leader stroke.

Never been hit directly, but had a few episodes with high desert lightning hitting far too close for comfort during a decade as a missile research meteorologist. Sorta rattles your cage for a while afterwards.

The most scared I've ever been regarding a potential lightning strike was when I was on a motorcycle trip in the late 60's. I was riding from Utah to Reno on my trusty Sportster through scattered thunderstorms the whole way. Lightning was striking as close as a few hundred yards away and the deafening crack of thunder was heard a couple of seconds later.

There was no place to hide as far as the eye could see, just low rolling desert hills not much higher than my head. Nonetheless I laid down on the tank and bore through it.

Next time I see anything like that on a motorcycle, I'm making a U-turn and waiting it out.

Thanks again for the advice, very much appreciated.

Dan

here's a lucky girl:

Approximately 9/5/03 15:20, searn uttered for posterity:

For fairly loose interpretation of "lucky" here is another one: