Cars and Lightning

leon · #1 05-08-2015, 02:38 PM

Hi Guys

It is my intention to travel back to the top end during the wet season, and do some serious storm chasing.
I have been their before, however I was parked up for a considerable time and enjoyed all the light shows, with out actually driving anywhere.
This time i intend to travel throughout the territory during the storm months and capture lightning at its best.
I will probably be out in some remote areas with my vehicle and was wondering how much if any damage a direct/near strike could cause to the cars computer and electrical system.
Would it be wise to disconnect the battery/isolate the power to all the cars electrical system before the storm approaches

I have seen some serious strikes up there

Many Thanks.

Leon

torana68 (Roger) · #2 05-08-2015, 03:57 PM

guess you've googled? never seen it go through a car but have seen it shred a gum tree.
http://www.lightningsafety.com/nlsi_...le_strike.html

leon · #3 05-08-2015, 04:05 PM

Yea Roger I did see that one, thanks for your response.

Leon

Chif (Andrew) · #4 05-08-2015, 04:10 PM

I'd play it safe and disconnect the battery. Your chassis is used as a ground so there'd definitely be a path to the battery and therefore electronics. At the very least I imagine it would blow all you fuses and cause a headache in that regard. In saying that I've seen cars / trucks being struck as they're driving on YouTube and they carried on going.

I hope you have fun and capture some good images. Sounds like you'll have a great time.

julianh72 (Julian) · #5 05-08-2015, 04:13 PM

I can attest from personal experience (sitting in an old Holden under the UQ Electrical Engineering department's High Voltage equipment for a discharge of a few hundred thousand volts) that being inside a car is perfectly safe, as long as you don't touch any of the metal work (door handles etc), as the car's body makes an excellence protective Faraday Cage.

As for the electrical equipment - it may or may not suffer any damage. I'm not sure whether disconnecting the battery would have any effect though - the induced surge currents are probably totally independent of whether the battery is connected or not. In the UQ's Holden, part of the demonstration was that the radio still worked after the shock, but electronics gear was a lot more "robust" in those days. Modern solid-state electronics can get fried with just a few volts / milliamps in the wrong place (which is why you need to wear an anti-static grounding strap when working on sensitive electronic gear).

http://www.lightningsafety.com/nlsi_...le_strike.html

leon · #6 05-08-2015, 04:37 PM

Thank you, Julian you are probably right, the connected or disconnected battery would possibility be of no importance.

Leon

Baddad (Marty) · #7 05-08-2015, 04:52 PM

Hi Leon,
I would not worry about doing anything like disconnecting the battery etc.

As Julian pointed out the car is a Faraday cage. The power tends to flow on the outer skin of the car. Each "packet" of energy is repelling each other so it is unlikely for it to enter the internal circuitry of the vehicle.

Having had some conversations with commercial aircraft pilots it is also the case with planes. Pilots say it is common for lightning strikes to planes. The remain flying.

One case I know of was where a car was struck and the driver stopped the car. He was told to gently move the car up against the wire fence. Sparks flew as the "capacitance" discharged. That may be the only danger from lightning that I assume would gradually discharge given a wet situation.

I think that disabling the car by turning off the battery is a mistake. The bigger danger from storms is big hail. You need to move quickly away from a hail front. Even worse is the possibility of an asymetrical micoburst. These are scary. Tree branches get ripped off etc. You need a quick get away.

That's my 2 bob's worth and it comes from informed sources.

Cheers

Wavytone · #8 05-08-2015, 05:21 PM

On both of our cars (recent Mazda and Honda) if I disconnected the battery the car would be immobilised so it's not really a viable option. In the case of the honda which has a CVT, this also erases the CVT gearbox programming which means no driving till that's fixed too, at a cost of some $500. I found out the hard way once with the Honda's battery going flat as it is driven very little, and I also asked our Mazda dealer about the mazda 3 we have.

Lightning usually strikes the highest point of an object. The analogy to a Faraday cage is valid if the lighting strikes the car body, but not valid if the lightning scores a direct hit on an exposed wire connected internally inside the body - and a car antenna is one example, I mean the sort that stick up from the car roof as our Mazda 3 has, as well as many other cars.

If the lighting scored a direct hit on the antenna it would probably destroy the sound system and possibly the CAN bus it's connected to in the dash, and anything connected to that. Probably a good idea to keep your hands clear of the electronics if your car also has a rooftop antenna.

Some cars - as our Honda - have the antenna embedded in the windscreen or rear window - sensible place as lightning will hit the body first.

Exfso (Peter) · #9 05-08-2015, 09:07 PM

No need to worry about hail in the top end, I lived over 16 yrs in both Darwin and Katherine, never saw hail, but did see some massive storms and rain drops. The hail melts before it reaches the ground up there.

FlashDrive (Poppy) · #10 05-08-2015, 10:23 PM

a near by ' strike ' could pose EMP ( Electro Magnetic Pulse ) it's known to ' induce ' some ' nasties ' to electronic components.

but then again ... you could get away with no problems.

Col...

xelasnave · #11 06-08-2015, 08:47 AM

Hi Leon
Have you considered hunting for upper atmosphere lightning. There are a few distinct types called elves, sprites jets.
There is a little about them here..
https://en.m.wikipedia.org/wiki/Uppe...eric_lightning
Not sure about the cost of gear to capture them or if there is anyway to capture them up where you plan to go but it seems interesting.

multiweb (Marc) · #12 06-08-2015, 10:45 AM

Quote:

Originally Posted by leon

Hi Guys

It is my intention to travel back to the top end during the wet season, and do some serious storm chasing.
I have been their before, however I was parked up for a considerable time and enjoyed all the light shows, with out actually driving anywhere.
This time i intend to travel throughout the territory during the storm months and capture lightning at its best.
I will probably be out in some remote areas with my vehicle and was wondering how much if any damage a direct/near strike could cause to the cars computer and electrical system.
Would it be wise to disconnect the battery/isolate the power to all the cars electrical system before the storm approaches

I have seen some serious strikes up there

Many Thanks.

Leon

In any event if you get a direct hit I suspect you'll need a set of new tyres.