Lightning vs Car vs You

[Radio]

What happens when lightning hits a car...with you in it?

http://abcnews.go.com/US/lightning-s...ry?id=31497055

You will likely survive.
The car will likely not survive. with all the electronics blown out, half the windows, a couple of tires and the air bags.

In fact, it may even burst into flames.

A sturdy building is your best bet.

[N3LYT]

Faraday shield.

[NN5I]

A metal car body is indeed a pretty good Faraday shield -- most of the time -- but not necessarily during a lightning strike.

First, let's wonder what resistance might exist between the floor pan and the roof. I'd think it would not be less than about 0.01 ohm. Could be much more if body panels are poorly bonded.

What's the current in a lightning bolt? References that I've seen say typically about 30,000 amperes, but often as much as 120,000 amperes.

Now suppose that lightning current is flowing upward from ground through your car, because the lightning bolt chose your car as a target. Say, 120,000 amperes through your car body's 0.01 amperes. During the strike, there will be 1200 volts between the floor pan and the roof. Your feet are on the floor, and your head is near the roof.

Will that Faraday shield protect you? Eh? Oh, OK. I don't think so either.

[Radio]

Originally Posted by NN5I

Will that Faraday shield protect you? Eh? Oh, OK. I don't think so either.

Proof's in the puddin'

The young lady in the video is still out walking around, sore ribs from being blasted by the airbags. And many others, to boot.

Seems the most likely way to die in this scenario is to be rendered unconscious and then the car catches fire from the strike.

Now no one is saying this is an altogether pleasant experience... and the video states the best place to be is in a substantial building.

[N3LYT]

The current flows around a Faraday shield so those inside should feel no effects well I know I would probably wet my self if lighting struck my truck but the occupants should be fine. There was a utube posting a while back that was caught on a video camera of a full size pickup in Canada getting struck pretty impressive.

[NN5I]

Originally Posted by N3LYT

The current flows around a Faraday shield

Indeed it does, but only when resistive and inductive effects are negligible. With lightning, because of the fast risetimes, inductive effects are important; and because of the very large currents available, the effect of even very small resistances can be cause major surprises. For lightnng, a car body is a very imperfect Faraday shield.

Taking a generality you've read somewhere, like "current flows around a Faraday shield", and applying it to very anomalous events like lightning strikes, without bothering to understand what's going on, can lead to serious errors.

[N3LYT]

Don't know but aircraft get struck all the time and every one inside walks away (after they land of course) Has there been a case of lighting deaths from cars being struck I could not fine any hard evidence. The greatest casualties seems to be tires, electronics and radio antennas.

[Radio]

Just don't have the radio mic laying in your lap when lightning comes down the antenna.

[wa8yxm]

Originally Posted by Radio

Proof's in the puddin'

The young lady in the video is still out walking around, sore ribs from being blasted by the airbags. And many others, to boot.

They push air bags as a safety device but every accident where air bags deploy is an injury accident..What injury..Air bag deployment injury of course.

I've seen crashes that if anything were worse.. Where the only injury was some minor brusing from the seat belt.. SEAT BELTS SAVE LIVES.. air bags are dangerous.

And yes..(to another poster) Current flows AROUND you but at that level the EMP is enough to mess up not only the car's electronics but your brain and or nerves as well.

Best plase to be when lightening strikes is...... ELSEWHERE!!!!

[NN5I]

Originally Posted by wa8yxm

They push air bags as a safety device but every accident where air bags deploy is an injury accident..What injury..Air bag deployment injury of course.

One must ask, of course, what the injuries would have been without the air bags. Typically much worse, I think. Much worse. Much.

A young person very dear to me totaled her car (no lightning involved) in Oklahoma City about three weeks ago, just three days before her high-school graduation. She had some sore places from being hit by air bags, but walked easily during the ceremony. Without air bags she would probably have sustained serious internal and external injuries and brain damage. Thank you, air bags!

She had been working hard and saving up for a better car anyway, and was well on the way to having enough. Last week, with a little help from friends (including Your Obedient Servant NN5I) she purchased a pretty little blue 2003 Mustang, and henceforth will be a better driver. Many young people total their first car and learn from it. What they learn is that it can happen to them. This is worth learning.

As for lightning, how the heck can you avoid it? The very expression a bolt from the blue means a totally unpredictable event. The metal car body, acting as a sort of makeshift (and very imperfect) Faraday shield, usually helps a lot, but I wouldn't volunteer to be a test subject. Would you, N3LYT?

[N3LYT]

Lighting testing facility in Germany http://www.topgear.com/uk/videos/1614615896 This guy did.

[NN5I]

No comparison between that and actual lightning, though. Lightning would be tens of thousands of times the voltage, and hundreds of thousands of times the current. Lightning is not a publicity stunt.

[N3LYT]

Well the Germans think enough of it to test power line equipment. Granted it doers not have the power of a lighting strike but the effect is the same.

[wa8yxm]

NN5I as I said I have seen.. or heard of hundreds and hundreds of accidents in 25 years to telling cops where to find them..ONE TIME.. Just once.an air bag deployed without injury.

I've seen many accidents that made that one look like a bumper kiss.. including one where A patrol car was involved and looking at the car I ask when the trooper's funeral was.. The Trooper behind me said he hoped not for a long time yet since he was driving.

No injury beyond seat belt bruse.

SEAT BELTS SAVE LIVES

Air bags have killed.

[NN5I]

Whatever you say. Cheers.

[W9CMG]

"ONE TIME.. Just once.an air bag deployed without injury."

Maybe I'll buy a Lotto ticket since I've had them deploy twice with no injury from them. Both times however, we had seat belt rashes.

[Radio]

We have had two deployments:

My son in a Ford Ranger. Not a scratch. Maybe a couple of rashy places. No big deal.

My wife in a Dodge mini-van. Just about broke her arm.

I always seem to get hit from behind so I wouldn't know.

[wa8yxm]

In the case of the car hit by lightening.. W/o Air bags. No injury period.

In the case of the young lady who MADE IT to Graduation

Did she have her seat belts on? If so they saved her life.. not the air bag.

[N3LYT]

Takes both to make it effective.

[NN5I]

Originally Posted by wa8yxm

In the case of the young lady who MADE IT to Graduation

Did she have her seat belts on? If so they saved her life.. not the air bag.

I'd have to have magical powers to know whether that's true or not.

Since I don't have any magical powers, I guess I must take the word of one who has.