Mobile Antennas: Attracting a Lightnig Strike

[Rob Wadsworth]

Mobile Antennas: Attracting a Lightning Strike

Cell phone, HAM, AM/FM antennas; are they worth having so many so close to severe storms without inviting a meltdown?
Or worse - the loss of the entire vehicle electrical system - leaving you stranded on a dirt road during the narrow window of the chase season in Whereami KS?
Even if you have a AAA card or your auto insurance covers the damage - is there any real options to lessen the loss of damage to equipment and the possible indirect lightning strike one may receive?

Would an internal tape antenna on the windshield alleviate the need for the external AM/FM antenna?
Anyone know?

Would having a passive radiator cell antenna eliminate the need for the antenna wire from coming in to the vehicle.
Thoughts?

HAM's are the only ones that don't have an option to this dilemma.
Yes/No?

I'm all for making chasing safer, and like any other situation that comes up - we must adapt and overcome - or be thought of as fools that chase storms waiting to get struck by lightning - as some see us.
I'm all for any suggestions and ideas that can make it safer or be done better...

 

[Brandon Sullivan]

To put it simply. in a matter of safety then yes them smaller undercover like antennas may have an advantage. but you will never see the same performance. i would rather have bigger antennas so you get great performance when not getting struck by lightnin

 

[Scott Weberpal]

Of the hundreds of people who chase, I've only heard of two or three vehicles which have been struck by lightning (not to say there haven't been more). I honestly don't think you are any more of a target with antennas than you are without. I have, numerous times, seen lightning strike with 50-100' of a chase vehicle with tall antennas and hit the edge of a flat field. I think getting hit by lightning, even with antennas, is more random chance.

 

[Dennis Sherrod]

Here is a link to some surge / suppressors for antennas.

http://www.wifi-link.com/product.php?class1_id=13&class2_id=30

 

[Rob Wadsworth]

I've both seen and read that lightning strikes to a vehicle can also cause a pinhole in tires as the current runs to ground - causing flat tire(s).
But that is probably only the least problem that one encounters after a strike.
Being indirectly struck can cause arrhythmias, headaches/backaches, and irregular breathing.

The vehicles wiring harnesses can be fried, battery explode, and whatever equipment in use can be fried.
Is the surge protector proven to work in the field?
Any experienced chasers been there/done that?
Can they be wired to all chase items - or is it best to isolate the vehicles electrical system as well?

 

[Jason Foster]

A risk you have to take....as a storm chaser.

A direct hit is the real danger. One video has shown that, and I remember tires being blown out, and radios being useless. However, the passenger seem OK. But a direct hit is extremely dangerous.

That said, I have on many occasions, being communicating during a chase and felt a shock (yeah...it hurt) while holding a microphone or HT connected to an external antenna during CG strikes within a few hundred yards, so there is still dangers even when not directly hit.

But, as others have stated, it just the risk you accept when chasing. It is one of those things that most will not compromise on communications ability. Storm chasing is all about accepting unreasonable risk. However, if someone were to go the other route, and not have antennas, and such on the outside of the vehicle...that is acceptable too, just they will not be able to communicate as well.

 

[Dan Robinson]

Attraction of a lightning channel only comes in to play when it is already in very close range. The theory is that the lightning needs to be closer than a distance equal to the object's longest dimension. That is, if your antenna reaches 10 feet high, the stepped leader needs to be already descending virtually over your head (within ten feet horizontally) to be drawn to the antenna. The taller the object, the greater this 'attraction radius'.

As Scott pointed out, it is common to see cloud-to-ground strikes connecting to the ground within feet of a nearby metal object. For all intents and purposes, nothing on a vehicle (or on your person, such as a tripod or umbrella) will attract lightning unless you're already within feet of the strike to begin with.

 

[Jody Radzik]

On a chase in New Mexico last spring, I heard my antennas buzzing when the updraft I was chasing approached. As it got closer, the buzzing got louder. It was definitely a bit frightening, although the CGs were far enough away to keep me from scrambling.

 

[John Erwin]

One thing that can be done is to improve the DC bonding all over the vehicle. Most folks will not bother to go to all of the trouble of doing this, however many ham operators that run mobile HF have likely already encounted the need for this, although for slightly different reasons.

Basically it involves running bonding cables between the vehicles main components, especially doors, hood, trunk and exhaust system. Doing so equalizes the potential between all of the vehicles metallic components. Something else that needs to be considered is how your antenna's are mounted. This is where permanent mounts afford more protection since they are electrically bonded to the skin of the vehicle; mag mounts are not, and there is no extra wire outside of the car. For added protection the antenna can be protected with a lightning arrestor so that excess charges can be shunted to the car's skin.

What we are trying to acheive here is something akin to how aircraft are configured. They are often struck by lightning, however the charges most often flow over the skin of the aircraft and continue on towards the ground. This setup works most of the time because aircraft are painstakingly bonded all over the place. Still, a direct hit will exploit any difference in potential it can find.. so even an elaborate system such as I've described will likely still see some damage.

I've never lost a radio due to any nearby strikes (never been struct directly) however I have had to replace 3 different lightning arrestors (2 at home, 1 in the car). Good insurance in my opinion.

 

[Rob Wadsworth]

Well thanks guys - for all of your input.
I think the gamut of possibilities has been expressed to this question/dilemma.
YOU CAN BE SURE that I have no intention of wrapping myself in aluminum foil and playing with a Frisbee under a Meso the next time I go on a chase!
I am looking for safe alternatives to an activity that is inherently dangerous to begin with!
I asked for specifics on alternative wiring concepts - and got just that - too!
Many Thanks!