Car Magazine-Thunder Storms-Cars24.in

Lightning Strikes without Consequences

Lightning discharges , ever since a impressive but scary spectacle of nature. With the appearance of all steel car bodies about 100 years ago at least car drivers had an "all-clear". You have here the possibility to analyze the reason for that calmly before the next thunderstorm...

The Faraday cage	Limousines
Plastic Car Bodies	Without roof?
Bicycler	Conclusion

The Faraday cage

During lightning discharges voltages up to a few hundred million volts with currents between 10.000 and 20.000 ampere (home grids are designed for a maximum of 15 - 25 ampere with 250 Volts) are generated. So: high danger for humans outside the house which is protected by lightning arresters? For pedestrians and bicycler yes, the passengers of a car have it, if they observe a certain line of conduct, clearly better.

We have to thank the English man Faraday who gave us the scientific explanation for that . He recognized long before the invention of the automobile that staying inside a tin housing, which can also have the structure of a cage, is harmless namely as long as contact with the metal in the inside is impossible. Who wants to witness this "live" can do so in the German museum in Munich (and after that one can take a look at the original, the first automobile, the "Benz Patent motor vehicle, which as a motorized open wood carriage can not be counted as "lightning-resistant").

Top

Limousines

Normally we are sitting in cars with a closed tin car body, which corresponds exactly to the mentioned cage-principle. So: do we have an all clear? A few things have to be taken in consideration though: Don't choose high points as a parking place during a thunder storm, close windows and sunroof, retract if possible all antennas (in case of a case this could be critical for the connected electronic devices and their wiring), don't use the cell phone and respectively separate it from the antenna. Inside the car one should not touch any metal parts which are connected to the car body which because of today's standard plastic covering should not produce much problems.

If ,which normally does not happen very often, a lightning really strikes the car, it is possible that the passengers caused by the glaring and banging are frightened . For the car possibly the whole scene can end a little bit different: During tests in high voltage laboratories ("real" lightning cars are really hard to get) there were scorch marks on lacquer (punctual at entrance and exit points) and across the tire walls (according to the lightning course leading to the ground).

Top

Plastic car bodies

An aluminium automotive body shell or a plastic sheeting on a metal framework (popular construction principle for recreation vehicles but also for former models of Renault "Espace" or the "Trabbi") works also like a "Faraday case". Critical would be an all plastic housing, which is barely used in vehicle construction, at the most for single components (evite alcoves during thunder storms!).

Top

And without a fix roof?

The first measure is, even if it sounds unnecessary: please close the convertible soft top. If that's done the principle of Mister Faraday works here, too: In almost very soft top construction you can find convertible top bows (bars) of metal, which discharge the strike of a lightning via body and tires to the ground. Also windshield frames , rollover bar and top mechanic have a positive effect here.

This is also proved with simulations made in laboratories: According to this simulations scorch marks in the folding top material are not always to be excluded, though for the passengers, in this case test dummies, the consequences were totally harmless. Messages about accidents with convertible passengers in a real thunder storm do therefore not exist.

Top

Bicycler

There is only one advice (like in general for pedestrians, too): Avoid exposed spots and closeness to high objects (trees, masts) and if possible seek shelter under bridges or similar, keep distance to the machine, on an open field get yourself in a crouch position.

Top

Conclusion

During thunder storms most of all poor visibility, hailstorms, squalls, aquaplaning, torn off knobs and other obstacles on the road, are dangerous for motorized traffic participants. Statistics reveal that continuous victims of lightning ´strikes are pedestrians, wanderer, sportsmen, worker in external work areas, but just never motorized traffic participants. Nevertheless it's good to know how lightning strikes effect on vehicles and what to take into account.

Top