Third Disaster - A Direct Lightning Strike



Bless Farmers Insurance once again for their full coverage of this damage. It totalled $7,000 and I have lots of visual pictures to show what a direct lightning strike can do.

It was Labor Day weekend, 2000, and a very strong thunderstorm was going through Foxfield at 1:30 in the morning. There were many close hits and I was lying in bed praying that none would hit us. Sure enough, POW!!! And I knew instantly that this was not a near miss. That sinking feeling again, that every ham knows occasionally. The smoke detectors went off for about two seconds, everything went dark and quiet except for a crackling sound. Almost a sizzle and then it faded away. It smelled like ozone.

We were both up like a shot to check out the damage. I had a lot of protection installed so I was pretty confident that not too much had been hurt. It turned out that everything that had protection was fine. Those items that somehow had missed being protected were wiped out.



This is the control in the garage where the lightning came inside. Notice the scorch on the housing and the garage door opener wires vaporized.

The lightning came into the house on those white Romex wires. They make up the line that runs power to the motororized folding plate. I had put a plug on the end and left it separated from the house wiring by two feet. I thought that two feet would be adequate separation but instead that turned out to be the breach.



Here we revisit the same outlet from above but with the transformer removed to show more of the scorch. This is apparently the point where the lightning entered the AC lines and went on into the house.

The reason the strike was especially damaging was because lightning jumped from those white wires to the telephone lines and AC wiring inside the garage. The phone line protection is on the outside where the lines enter the house. Therefore lightning was past the protection and free to do all the damage it wanted. That is where the most damage occurred. Lightning ran into the ISDN equipment, wiped it out, continued on out the LAN wiring throughout the house into four different computers. It wiped out the LAN board and the motherboard on all four computers. That's where most of the money came from on the insurance claim.

It left a permanent purple color on the big screen TV, and it wiped out the finals on my new ICOM IC-756PRO.

Lightning does some amazing things. This picture shows where the lightning was searching for any kind of a path to ground. This little metal bracket isn't attached to anything and yet it has scorch marks. It must have had enough inductance to look like a ground for an instant. Inductance has the characteristic of resisting instantaneous change in current(di/dt).

My friend, Bill Burick, AC0VC, says after his strike he was finding damage as much as 6 months later. I thought we had found it all til one night in December. All November we had been running our electric blanket but I was never really warm. Then we had a real cold snap in December and I began to realize the blanket wasn't working at all. It had been plugged in when the lightning hit and wiped out, not to be discovered til three months later.



This is the exact point where the lightning struck. It is the center of the beam at the top of my tower, up 105 feet. These were the only scorch marks on the tower and antennas.

My neighbor, Jan Abbott, says she just happened to be watching the storm from her window when my strike occurred. She says she saw the bolt strike the top of the tower and then she saw a stream of sparks for about 3 seconds afterward. She said it looked like fireworks.















An extreme closeup of the point where the lightning bolt hit. Notice the scorch. I am amazed that it was only scorched and not vaporized.

Little by little, a little later we had replaced or repaired everything that was damaged with the help of our insurance company. I am back to normal now with only pictures and memories to tell the story.



Hopefully this is the last "disaster" for me for a long time.

2002 Update: Of course, I realize that when I use the word "disaster" that it is tongue-in-cheek. I mean I know it's not really a disaster in the big scheme of things. September 11th puts a lot of things into perspective and many of us begin to understand that our "disasters" are really not too big a deal.

Improvements To Protection



I have since installed a disconnect for the power lines at the base of the tower. Now those lines that brought in the lightning are connected only when I am lowering the tower.

Next, I have installed telephone line and LAN wiring protection at each computer and the ISDN device. If lightning does strike again and comes in on the phone lines it will be arrested at each computer. I will keep my fingers crossed.

2008 Update: We have had no further "disasters", thank goodness, and are way over due. We don't have our ISDN line anymore but we still have ethernet surge protectors plus power line surge protectors on all our computers.

2011 Update: An onsite evaluation of our installation was done last summer by two professional lightning protection engineers. They made some interesting observations that I am implementing. Number one was the tower. It needs the ground rods connected together(bonded) in a ring, using copper strap. Number two, the number 6 wire between the tower and the house is inadequate. It needs to be replaced with copper strap. Number three, the connection on the vertical also needs to be replaced with a strap. In general the installion looks pretty good except for the those bonding upgrades needed. One general principle they emphasized is that the tower must provide the main grounding for the house and not the other way around. Considering that, the bonding between the house and the tower needs to be capable of carrying a fault (lightning strike) without fuzing (melting). Waiting for the next thunderstorm, as always...


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