How dangerous is an outside antenna ?

Nils Franke

Enthusiast
Joined
Apr 19, 2012
Messages
9
Location
Karlsruhe, Germany
Hi,

we are using magnetic outside antennas during chasing for signal amplifier and mobile thread net. Usually when driving through storms with lightning activity, we get the antennas in.
What do you think would happen if the antennas are left outside and the car is struck by lightning?
Would that just kill the hardware the antenna is connected to or would it be really dangerous because it could lead the strike into the car and hurt you?
We had some chases where we forgot to get the antennas in and could not stop, and we were really scared of a bolt coming in. Is that possible?

Cheers

Nils
 
If your vehicle gets directly struck by lightning, an antennae on your roof is the least of your worries. In many cases the lightning will completely destroy the electronics of the vehicle, kill the engine, and lock you into the car. Anything plugged in / touching the chassis will be fried as well. If you are lucky you'll be insulated from the bolt.

Most of the close call strikes I've had haven't been right under the storm (where you'd remove the antennae), but rather quite far away from the rain shaft or RFD. I've had bolts from the blue hit signs over my vehicles and leave craters in fields next to me whilst I filmed outside the car. Frankly, I wouldn't worry about it, if it happens, it happens.
 
Just last year my vehicle was almost struck twice on different chases. I'm talking really really close. One of the strikes hit a transformer right next to my vehicle as I was driving and sparks flew everywhere, it was pretty nuts. I actually get fairly nervous when a CG barrage starts heating up and bolts start flying everywhere. As Royce mentioned, I have heard that a direct strike to the vehicle can shut down the car and lock you in. That would be a pretty scary occurrence and possibly deadly if a fire starts. Some of the close strikes that I experienced last season actually have me thinking about having a hammer in my vehicle during chases, and I guess anytime during the convective season. As crazy as that sounds, if my car does get hit, and the electronics are fried, I want something to smash out the window and escape if needed. As far as antennae outside the vehicle, I am not sure if it would enhance your chance of the vehicle actually being struck, but I wouldn't be surprised that if the vehicle is struck, it would give the bolt better pathways to enter the inside of your vehicle.
 
One of my buddies had his car struck by lightening while he was in it. He was fine, but the car was totaled. Another friend had his boat hit and only had minor damage. The same friend sent me a picture he took in his boat where his daughter and her friend had their hair standing on end in a storm and thought it was funny. He had no idea how close he was to losing his daughter. His daughter and friend both had hair halfway down their backs and to see that hair literally standing on end was frightening.
Honestly, if I'm inside the vehicle I have zero concerns of a lightening strike. I'm not sure how much of a difference a 12-20 inch antenna makes in attracting lightening, but I can't imagine it makes a huge difference. Bottom line is I'm not going to give it a second thought. As long as I'm safe I'm not going to give it a thought. In the extremely odd chance the vehicle sucks up some damage, I'll worry about it then.


Sent from my iPad using Stormtrack mobile app
 
The National Lighting Safety Institute has a good page on lighting and vehicles at: http://lightningsafety.com/nlsi_pls/vehicle_strike.html including an interesting quote:
What happens when lightning strikes a vehicle? The answer, gleaned from anecdotal observations, is all the way from "Nothing" to "Wow! What a mess . . . my car is a disaster."

I think we all need to think about risk here. Most often your car isn't the tallest best grounded object around, so more often than not something else will be what gets struck. You are probably at greater risk parking under a tree or power line and having it get struck and fall on your car. I agree with Todd, that a few extra inches probably doesn't make you that much more of a target. I would think twice about getting out of a car to take down an antenna. A lighting strike to a car with you inside is in most cases survivable. A lighting strike to your body when you are outside of the car taking down the antenna is a much greater danger, especially when you consider that the outer skin of the vehicle is where most of the energy goes when a vehicle is struck.

Lighting is a form of EMP (Electromagnetic Pulse). EMP does mess up electronics (both your car and the devices in it). In a major storm you might consider disconnecting the antenna from your devices inside the vehicle. After all that is what ham radio operators do with base station antennas and what people do with TV antennas (we don't climb up on the roof to take the antenna down during the storm). Although I should point out that even disconnecting the antenna inside the vehicle can be dangerous if you happen to be doing it at the time the vehicle is struck. I have seen online reports of police officers being injured when their car was struck and they where holding the mic to their radio.

In my case, I don't worry about it. When the storm is bad, that is often when I need my ham radio antenna the most. To me being out of communication is a bigger concern than the antenna getting hit by lighting.
 
Mike Marz, We ride with emergency hammer or life hammer that can break windows with ease and cut safety belts. Might be a good tool to pick up and have in vehicle.
 
Most often your car isn't the tallest best grounded object around, so more often than not something else will be what gets struck. You are probably at greater risk parking under a tree or power line and having it get struck and fall on your car.

Exactly and just the response I was going to give. Make a long story short, even if you do remove the antennas and the car is struck. Anything and everything that is attached to the vehicles electrical system will be fried and you will have bigger issues other than your devices being fried. You would need to disconnect all power from the devices and if you choose to leave the antennas out, then you would need to disconnect them as well. The percentage of actually being struck is less than going through all that hassle of removing and disconnecting things. I have two 36" ham radio antennas which have better Db that the day to day run about town 11" antennas I use when I am spotting/chasing to try to limit the attenuation between storms and the repeater and I don't think twice about it because like was mentioned. My communication is more important to have than worrying about the off chance of getting struck. My radios are useless in spotting if I disconnect them just as your cell booster and threat net will be useless if you have to disconnect them when you really need them.

In regards to the door locks you should only have to worry about this on older vehicles. I don't remember the exact year but I believe around 2006 I want to say maybe. Through the USDOT Integrated Vehicle-Based Safety Systems (IVBSS) one of the many safety features which was requested to manufactures was that all new vehicles be equipped with integrated safety systems. One of those safety systems is manual door lock overrides. Different auto makers have several different methods for applying this depending on the situation. There are many different safety features but, in regards to an electrical power loss. Vehicles with power locks have been equipped with manual door lock mechanisms just like cars without power locks would have where you can manually lock and unlock from inside the car. If the vehicle isn't equipped with a manual door lock then simply lifting the door handle from the interior will unlock the door manually. These are the most common methods on newer vehicles but I can't remember exactly when it was implemented. Other high end auto makers have even more safety features to this regard but generally all at least have this simple method in addition to their other methods they might implement for different situations and redundancy. Now if you have a vehicle that automatically locks your doors when your car is started. You can take this to your dealer and they can flash the PCM to disable this feature free of charge. This has been required by USDOT to do so as part of the IVBSS.

I ran a call one time for a lock out. Which isn't uncommon but, rare since I am a VFD in a rural area so we don't get many of them and usually PD handles it. When we check on scene we discover the person was locked in the vehicle and not locked out and it was in the middle of the Texas summer, which explains why we were dispatched because it wasn't a typical lock out. The car was equipped with the auto door locks that locked the door when the car was started. The car had a bad alternator as we learned later but, when the woman tried to get out the battery was dead so the doors would not unlock. Some do when you turn it off and some don't or they will unlock when you put it in park. Hers happened to be the one that didn't unlock until the car was shut off. So when she shut it off the battery was drained so much it didn't have enough power to unlock the doors so she was locked in, or so she thought. We go Ma'am do you see your door handle, yes she replies. Lift that handle. Click click, door unlocks and she opens the door. She was so embarrassed. Moral of the story, check to see if your car is new enough that it has one of these safety features before you call 911 or bust out your window and if have the auto door locks and want them disabled. Then just take it to the dealership and they can disable the feature. Might save you a couple hundred dollars from having to replace your window if you bust it out and prevent you from having a wet ride home if your car is still able to be driven.
 
As Royce mentioned, I have heard that a direct strike to the vehicle can shut down the car and lock you in. That would be a pretty scary occurrence and possibly deadly if a fire starts.

I have not heard this before. I'm skeptical. In every car I've ever driven, every single front side door was manually unlocked when the door lever was pulled. It would make absolutely no sense for a car door to be un-unlockable when it has no power - that means if you took the battery out of the car you wouldn't be able to open the car from the outside, which means if you for some reason closed the door with it locked, you'd essentially have locked yourself out of your car even if you have your keys. That can't be right.

In response to the OP, I use the general safety precaution that lightning can and will use any wired or metal device that goes into your cab to hurt you. When I encounter close CG barrages, I unplug all of my power cords/cables and keep my hands off the instrument panels (radio, HVAC etc). If you keep your hands off of metal or electronic items, your chances of being impacted or hurt in the event of your car being struck should be at a minimum.
 
From 2 years ago, you probably saw this video - http://abcnews.go.com/blogs/headlines/2014/06/watch-lightning-strikes-moving-truck/

"A fireball enveloped the truck, melting part of the metal and burning away two craters into the the road. The Perry's were trapped inside, unable to open the doors or windows, which seemed locked, as smoke filled the inside of the cab."

I guess I stand corrected.

I suppose my statement was more for having the locking mechanism "deadened" by a loss of power rather than what this case appears to be - having the metal melt so that the locking pin or something in the door mechanically wasn't operable anymore...but in the end it results in the same trouble for the occupant.

I guess in general it's worth the risk to me. I don't want to be taking half a garage worth of tools with me when I chase.
 
I guess I stand corrected.

I suppose my statement was more for having the locking mechanism "deadened" by a loss of power rather than what this case appears to be - having the metal melt so that the locking pin or something in the door mechanically wasn't operable anymore..

In my opinion I wouldn't say your comment was in correct or invalid nor was mine. The original statement was that if the vehicle lost power you'd be locked out. Under normal circumstances with only the loss of power alone is not going to cause you to be locked in your vehicle in the newer vehicles that are equipped with the Integrated Vehicle-Based Safety Systems.

In this case this is a different circumstance than just the vehicle losing power as other factors came into play. I have read some other articles on this story and the details and facts are vague from story to story as the gentleman stated the power system was fried which led him to believe that locked them in. In some of the articles there was more details that stated the roof and frame was rippled. This is no different than getting in a motor vehicle accident which would cause frame damage and cause the door to be jammed. So the frame damage from the strike alone could have caused the door to be jammed. Also in this case which you mentioned and was one of the first things that came to my mind. You take a strike like that it could have essentially melted the metal and possibly caused the door mechanism to practical weld itself causing the door to not open. I believe there was other factors in this case that caused the door to be jammed rather than just the loss of power alone but since there was not many details or facts regarding how they got locked in only one can assume. If I was a betting man, I would be willing to bet there was other factors other than power loss that caused the door to be jammed and not able to be opened.

At the end of the day I think we can all agree that it would be a smart choice to carry a multi tool like was mentioned for glass break and cutting the seat belt. As mentioned these tools are inexpensive and can be used in many different scenarios. This is just one of the hazards with chasing storms. If it happens, it is going to happen and there is nothing we can really do to prevent it and that is the one thing that article did prove as it could happen to anyone antennas or not. What we can do is be prepared in case this event ever happens and you need a way out that could save your life or someone else's.
 
Lightning doesn't necessarily strike the tallest thing around. And another two feet of metal won't make you a more attractive target. That said if you're going to get struck it will most likely come in through a pointy object like an antenna. I've moved my antenna wiring mostly out of the cab as I don't want to be anywhere nearby if that happens. And I've verified my antennas are well grounded so charges will be drained off as quickly as possible. When I ran a mag-mount antenna I once had charges build up under a thunderstorm enough to cause sparks inside the cab. No problems with my NMO mount and hitch mounted antennas.
 
I had always wondered about this being a safety hazard. I recently heard an anecdotal report from a guy who knew a guy.. take it for what it's worth. He was a chaser with antennae, and his car was struck by lightning. He said part of the lightning came inside, traveling down the cable to the handheld radio next to his chase partner's leg, and the lightning jumped to his leg and went down to his foot before exiting the floorboard. The guy was injured but okay.
 
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