What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Lightning Strike

czechsix

czechsix

Well Known Member
2nuhiit.jpg


2wrjnh4.jpg


2z4iqgo.jpg


Here's some pics of the top of the vertical stab of my RV-8A that I took with my cellphone camera yesterday evening. I flew the airplane from Kansas City out to Virginia to spend the 4th of July weekend with my inlaws and left it tied down on the ramp at Blacksburg/VA Tech airport (KBCB). When I did the preflight inspection to depart Blacksburg on Tues morning, I noticed a black lump up on the tail and thought it was a bird dropping. Blasted featherdusters, why do they have to poop on my airplane? Anyway I figured I would clean it off later. Got in the airplane and started it up, and discovered that the alternator was offline. I thought this was odd since it was working fine when I shut down a few days earlier. Cycled the breaker and Alt field switch with no luck. Since I have dual batteries on board I elected to make a 1 hour flight down to where my parents live in NC, just south of Charlotte (JAARS Townsend field, N52), where I knew I could get tools and help to troubleshoot the alternator problem. Upon arrival I borrowed a voltmeter and figured out that the problem was a failed voltage regulator, so I ordered a new one next-day-air from B&C and installed it Wed morning. This fixed the problem and I had an uneventful flight back home to Kansas. After wiping the bugs off, I climbed up on a stool to clean off the bird dropping on the tail, and realized it was actually a hole melted in the aluminum and fiberglass, obviously from a lightning strike. I called the Blacksburg airport and the line boy confirmed that the airport had been hit by lightning during a t-storm that blew through on the afternoon of the 4th, but he was not aware of exactly where the strike occurred. I inspected the rest of the airplane to see if I could find an exit point for the other end of the lightning bolt. So far I haven't found anything. The tiedown ropes may have been wet enough to conduct the current to the ground without burning. It's interesting that the voltage regulator (mounted on the firewall on the opposite end of the airplane from where the lightning hit) was the only electrical component damaged. Everything else seems to be working just fine.

Anyway, the irony of the situation has not escaped me. Struck by lightning, on the 4th of July, right next to the lightning bolt graphic I put on the tail. Moral of the story: don't tempt fate by putting a lightning bolt on the tail of your airplane, and then leaving it outside in a thunderstorm. :)

----------------------------------------------UPDATE---------------------------------------------

Well the mystery of what happened to the other end of the lightning bolt is no longer a mystery. I pulled a bunch of panels and fairings off the airplane and found arcing damage on the outboard rim of both wheels. The damage to the right wheel is fairly minor, the damage to the left wheel is more severe, with two melted spots on the rim. No damage to the tires or tight-fitting fiberglass wheel fairings.

2d0g8q0.jpg


18eweu.jpg


Sounds like my insurance company is willing to pay for all the damages (no deductible) which looks to be amounting to well over $1K at this point...

Mark Navratil
RV-8A N2D
Olathe, KS
 
Last edited:
Mark,

Wow, some pictures. Next time, take the #1 iron out of your golf bag or borrow one if you don't have one. Lean it up against the side of the plane next time you park it outside. Why? (old golfers joke)

'Cause not even God can hit a 1 iron!

See you and Skyler in Oshkosh in a couple of weeks.
 
Further advice.

My Air Tractor with a PT-6 turbine was sold to a guy in central Georgia, who used chains and an over center bucking bar to hold it tight.

He parked it one day, due to T-storms and bucked it down. Next day, no starter, so it took a day finding and installing another one....then the electric fuel pump wouldn't prime so another day spent.

He cranked the airplane and went flying and soon after, the chip light came on. The chip detector is in the lower reduction gearbox in the front of the engine and a piece of metal had bridged the gap between the two little magnets....yep, the gearbox was making metal!

Eventually, it took a gearbox overhaul...probably $50,000+ since the lightning had entered the top prop blade, through the #6 bearing (right behind the prop)..through the engine and starter/generator..through the fuselage and wings, to the well grounded chain!!

Don't ever use steel cable or chains to tie down your airplane.

Best,
 
czechsix said:
Anyway, the irony of the situation has not escaped me. Struck by lightning, on the 4th of July, right next to the lightning bolt graphic I put on the tail. Moral of the story: don't tempt fate by putting a lightning bolt on the tail of your airplane, and then leaving it outside in a thunderstorm. :)
Click to expand...

Sorry to hear about the lightning strike and damage, but I've gotta tell you that I laughed out loud when I read this. May be the funniest thing I've read on VAF in a while.
 
czechsix said:
Moral of the story: don't tempt fate by putting a lightning bolt on the tail of your airplane, and then leaving it outside in a thunderstorm. :)
Click to expand...

This is also why I've always said that I would NEVER paint Flames on an airplane or car.

On Lightning; I've dealt with lightning strikes on houses and I can assure you that lightning does NOT follow the rules!
 
What are the chances the lightening could have damaged a rod-end bearing, if it had hit on a control surface?
 
Pierrre- in a former life, I briefly flew the military version of King Air 200, and had an in-flight lightning strike. Reported it at the conclusion of the flight, inspection showed that it hit a prop tip.

The maintenance instructions required an engine change, which at the time surprised me. I was told that the lightning would have ruined several bearings in the engine, and that continued use would surely result in an eventual engine failure.

Don't know if the same holds true for recip engines????



pierre smith said:
My Air Tractor with a PT-6 turbine was sold to a guy in central Georgia, who used chains and an over center bucking bar to hold it tight.

He parked it one day, due to T-storms and bucked it down. Next day, no starter, so it took a day finding and installing another one....then the electric fuel pump wouldn't prime so another day spent.

He cranked the airplane and went flying and soon after, the chip light came on. The chip detector is in the lower reduction gearbox in the front of the engine and a piece of metal had bridged the gap between the two little magnets....yep, the gearbox was making metal!

Eventually, it took a gearbox overhaul...probably $50,000+ since the lightning had entered the top prop blade, through the #6 bearing (right behind the prop)..through the engine and starter/generator..through the fuselage and wings, to the well grounded chain!!

Don't ever use steel cable or chains to tie down your airplane.

Best,
Click to expand...
 
PCHunt said:
Pierrre- in a former life, I briefly flew the military version of King Air 200, and had an in-flight lightning strike. Reported it at the conclusion of the flight, inspection showed that it hit a prop tip.

The maintenance instructions required an engine change, which at the time surprised me. I was told that the lightning would have ruined several bearings in the engine, and that continued use would surely result in an eventual engine failure.

Don't know if the same holds true for recip engines????
Click to expand...

Did the plane have lightning bolt grapics? :confused:


;)
 
Double Strike

This lightening bolt was simply looking for some good company. When it saw the beautiful lightening bolt painted on the tail of your airplane, it was simply love at first sight.

I'm gonna call your plane "Double Strike" :D

And, yes, you better "Czech Six" from now on!!
 
Question:

PCHunt said:
Pierrre- in a former life, I briefly flew the military version of King Air 200, and had an in-flight lightning strike. Reported it at the conclusion of the flight, inspection showed that it hit a prop tip.

The maintenance instructions required an engine change, which at the time surprised me. I was told that the lightning would have ruined several bearings in the engine, and that continued use would surely result in an eventual engine failure.

Don't know if the same holds true for recip engines????
Click to expand...

Shouldn't there be an exit mark as well? If it's an in-flight strike, doesn't the current flow through the airplane and continue on? If so, I can understand the bearings in the turbine getting arced, if there's a mark on the prop blade.

Best,
 
Lightning current will only follow one path and that is the path of least resistance. Its likely your alternator was in that path.
 
Some years ago we had a C-150 sustain a lightning strike on the rudder. The rudder was "welded" in position, stuck. Safe landing, but a tough thing to taxi.

I pleased that, in this case, the strike went for the forward end of painted lightning. :rolleyes:

John Clark ATP, CFI
FAAST Team Representative
EAA Flight Advisor
RV8 N18U "Sunshine"
KSBA
 
when airplanes get hit in flight, the lightning travels through the plane. there is a "hit" point and and "exit" point.
here is a good photo
http://abcnews.go.com/Travel/lightn...rlines-jet-planes-destroyed/story?id=13586763

Years ago, I flew Twin-Otters over the Grand Canyon, every summer we would have a few planes hit by lightning. It was always the same, it hit on the wing or tail and exited on the nose strut. Most times the oleo was welded together and had to be replaced.

If an object gets hit on the ground there has to be an electrical path to ground.That is why you never hear of cars getting hit by lighting, ( the rubber tires)
The lightning usually hits the highest part of the object and the current travels through the object to ground. Wet rope is probably somewhat conductive, but if the lightning traveled down the rope it most likely would have burned the rope. An average bolt of lightning carries 30,000 amps!
I would take off the wheel pants and look at the gear legs and axles, they are the closest metal parts to the ground. It is possible the lightning traveled down the gear leg and arced to the wet ground.

If you want to know more about lightning, wikipedia actually has some very good info.
http://en.wikipedia.org/wiki/Lightning
 
Conductive vs. non-conductive tie downs

pierre smith said:
... since the lightning had entered the top prop blade, through the #6 bearing (right behind the prop)..through the engine and starter/generator..through the fuselage and wings, to the well grounded chain!!

Don't ever use steel cable or chains to tie down your airplane.
Click to expand...

Pierre, I think that point deserves more discussion. Are you saying there would have been less damage if the plane was tied down with non-conductive rope instead of steel cable or chain? It's not obvious to me that that's true. If anything, I would think that having a good conductive path to ground may have reduced the amount of damage by not having another arc departing the airplane to ground (an "exit wound"). If I'm wrong, or if I misunderstood your point, please explain. Interesting stuff!
 
Electrically the lightning found a path thru the airplane and it happened to be of less resistance of the surroundings. If non-conductive tiedowns were used then the airplane may not have been struck by lightning at all, but unlikely. Really no different than standing under a tree during a storm.
 
rocketbob said:
Lightning current will only follow one path and that is the path of least resistance.
Click to expand...

Well Bob, not necessarily. Like I said, I've experienced lightning strikes at home. One hit the very top of an antenna mast that was into the ground several feet. The lightning did NOT follow that path. It instead followed a guy wire that was attached to the roof. From there it jumped to a metal rain gutter and danced down it to the kitchen window, leaving burn marks about every 2 feet. This was witnesses by a friend who was standing there watching it.
It wiped out things that you would never expect and didn't affect things that should have been obvious.

Like I said, lightning doesn't always follow the rules!
 
Ohm's law has no 'lightning clause' in it. It is just that the path of least resistance is not always as obvious as we might think it is because we often fail to recognize all of the variables in play during a strike.
 
Isolated ground rods are actually pretty crappy low resistance grounds in a ton of situations....
 
I was cruising down the Q routes between LA and FL one night in clear smooth air at 450 on top of a pretty good set of storms when we got nailed by lightning coming up from below. No obvious damage or issues as a result but we took the airplane to the manufacturer in KSAV for a lightning strike inspection. They found the entry and exit holes in the lower radome and top of the tail respectively. After repairing these small holes, checking all the filters etc we were on our way. I don't recall the interval or duration but for a period after that we did follow up filter checks at home for a while in accordance with the maintenance manual.
Fixing the obvious might not be your only damage. Look everything over very carefully and monitor your filters for a while.
 
Entry or Exit Wound

Lightning usually starts on the ground and sends a streamer up into the atmosphere, so the melted metal on the VS most likely is an exit rather than an entry wound. There may be more damage where ever the plane came into close contact with the ground.
 
Last edited:
Wheel bearings can also suffer damage from a lightning strike. If a lightning bolt has just cruised thru 10,000 feet or more of the atmosphere, that couple inches of rubber tire does not make diddly squat of an insulator to stop it from going all the way down thru the landing gear.
 
Now that I think about it..

mfshook62 said:
....Lightning usually starts on the ground and sends a streamer up into the clouds, so the melted metal on the VS most likely is an exit rather than an entry wound. .
Click to expand...

I should have realized that lightning starts from the ground, since it's the negative pole, so the tiedowns (Roee) were the path of least resistance for starters, travelling upwards to the positive sky, exiting the highest of the three prop blades, in this case.

Best,
 
Lightning can travel from ground to cloud or it can go the other way.
(negative lightning or positive lightning)

read the wikipedia page about lightning, you will see that it is more complex then a big spark from the sky.

bottom line is a large current flowed through the plane. even if you find the exit point you still don't know what it flowed through. lucky most of the time in a metal airplane the current flows in the skin, that is why an airliner can get hit and nothing happens on the inside.
 
Interesting discussion.

I work as an aircraft maintenance engineer for a Canadian airline and I get to see aircraft that were hit by lightening almost every month. On Airliners, everything is bonded via bonding cables in order to dissipate static electricity and to give an easy alternate path to any static electricity that might otherwise travel through bearings.

Rarely do we ever find large damage. Usually an entry point is found with an exit point and in the worst cases, the electricity dances in and out along the fuselage giving us multiple entry and exit points. It is usually a matter of replacing a few rivets when damage is found but most strikes cause no harm at all due to the designs of the aircrafts.

?ric
 
John Clark said:
Some years ago we had a C-150 sustain a lightning strike on the rudder. The rudder was "welded" in position, stuck. Safe landing, but a tough thing to taxi.
Click to expand...

On Airliners, everything is bonded via bonding cables in order to dissipate static electricity and to give an easy alternate path to any static electricity that might otherwise travel through bearings.
Click to expand...

Aha! I always wondered about the true purpose of the bonding braids on control surfaces!
 
We used bonding braids.

Years ago, when we dusted with sulphur, we had to bond our control surfaces to reduce static electricity generated by the ailerons, elevators and rudder, as the air flowed over them. There were reports of airplanes catching on fire as the sulphur fire followed the airplane in the field, all the way to the hopper:eek:

The hinges often didn't/don't provide a good current path because of paint, nylon bushings in Heim joints and so on.

Best,
 
Interesting stuff! With lightning, and static electricity and arcing in general, there is a little bit of voodoo involved. I'm kidding of course, the laws of physics still apply. But as has been noted, lightning is a complex phenomenon, and analyzing or predicting its behavior is not at all as straight forward as a simple resistive circuit. That's why it's really interesting to hear the empirical observations of those who've actually experienced it. Good stuff.
 
My experience...

I had a couple experiences while in the military working around helicopters. The first time was a relatively minor lightning strike that resulted in burn marks on rotor blades (entry point?) and a couple of paint burns on the lower fuselage (exit points). The next aircraft sustained a major strike that entered the upper tail rotor blade (while tied down) and exited at various points on the aircraft. This aircraft had the tail rotor blade explosively blown apart, all of the gear boxes/transmission were strongly magnetized, and there were several burn holes in the lower part of the fuselage. Needless, to say this one was bundled up and sent to depot for a major overhaul...if they even bothered. For all I know it may be a part of my RV7 after they melted it down.

Bottom line....nothing stands in the way of Mother Nature.
 
I ran aircraft maintenance departments in the military and we had a number of lightning strikes. We always did a very detailed inspection of all bearings such as rod ends and wheels because it often welded them tight. All control runs were closely inspected. Helicopter gear boxes often went back for overhaul to look for internal damage. Inflight strikes were always better than on-ground strikes. In-flight strikes often left small entrance and exit burns and killed magnetic compasses.
 
You must log in or register to reply here.
Back
Top