Is it possible for an airplane in flight to be struck by lightning?

[KA1ZGC]

I can't imagine all systems on board an aircraft being disabled by lightning. We all know how lightning hits certain things and avoids other things.

...but none of us can say which things will get hit and which won't. Just because there's redundancy doesn't mean a backup system won't be equally damaged by whatever damaged the main system, no matter what the cause.

Since everything in an aircraft is tied together by wiring harnesses, that's all lightning would have to hit. Doesn't matter what else it hits. It doesn't need to directly strike something to knock it out of whack for a few minutes or fry it altogether.

I'm not convinced the wire mesh they put in these planes is up to the job. Unfortunately, the only way to find out is to get hit by lightning while flying one.

[Sam KS2AM]

747 and lightning strike video.

http://www.youtube.com/watch?v=5IRfbC0RHsY&NR=1

[WBear2GCR]

Unless there was an attack by giant hail stones, or even a sufficient quantity of medium sized ones, I vote for an improvised rapid exothermic kinetic energy device.

Lightning is very very improbable given the nature of the debris field... a disabled plane crashes down not out 35 miles. Afaik.

I read an account of how the guy with the "shoe" was supposed to work, and how the Pan Am flight and some other one was done in with liquid exothermic devices held by a suicide person in the cabin that were rather small and simple. Clever in fact.

This sounds like the debris field from the unfortunate "heat tile" space shuttle mission, eh?

Ah well, "...hooray for our side..." whatever side that may be?

                     _-_-bear

[KE6DF]

I was flying once coming in for a landing in Seattle during a storm.

During the approach there was a loud bang.

As soon as we were on the ground, the pilot came on and said that we had been hit by lightning.

Don't know if it damaged anything, but it didn't prevent a normal landing.

I'll ask my sister -- she is an engineer and works for Boeing.

In a related funny story, she says that one time they were testing an engine for damage from ingesting a bird.

They set the engine up on a test stand, and sent someone to the local supermarket to pick up some chickens to throw into the engine.

I guy they sent to the market came back with frozen chickens and threw them into the engine.

Did a lot of damage.

But the chances of encountering a frozen chicken flying is small.

[Tom WA3KLR]

My understanding is that there is also little chance of hail at 35,000 feet also.

[Fred k2dx]

Today the talking heads reported Air France had received a bomb threat for that route and held up a previous flight. That makes more sense I think, especially with such a huge debris field?

[KA1ZGC]

Lightning is very very improbable given the nature of the debris field... a disabled plane crashes down not out 35 miles. Afaik.

That's an awful lot of "very"s to be following up with an "afaik". Kinda defeats the purpose of the "very"s.

"I've never been more sure of anything in my life, I suppose".

"Out 35 miles"... from what? The debris was found almost two days after the crash. This is an ocean you're talking about, not a mud puddle. Oceans have waves, currents, and tides. They're lucky the wreckage was only spread out 35 miles. That says nothing about what took the plane down.

Remember Pan Am flight 101 exploding over Lockerbie, Scotland? It's a known fact that a bomb took that plane down. What hit the surface did so over an area not nearly so large as 35 miles.

The only possibility that can be ruled out at this point is Irwin Richardt shooting it down.

[Steve - WB3HUZ]

The only possibility that can be ruled out at this point is Irwin Richardt shooting it down.

Why?

[KA1ZGC]

The only possibility that can be ruled out at this point is Irwin Richardt shooting it down.

Why?

Fine. Meet me at Liberty corner with a shovel, and we can rule it out together. 

[Steve - WB3HUZ]

He was the only guy in the world named Irwin Richardt?

And, if Elvis can still be alive, so can Irb.   

[KA1ZGC]

I wonder what the Guiness world record is for the largest group of skydiving Irb Impersonators?

[W1RKW]

I don't know how fly by wire (FBW) commercial air craft systems are wired but the military FBW I work on, the cables of redundant systems are not paralleled next to each other and they use mil spec double shielded twisted pair for signal and command signals. I would hope that the FBW system on an aircraft is using double twisted pair as well and paralleled next to each other as well and hope their wiring provides another Faraday shield as well.  But again, I don't know how aircraft lay out their cables and want type of cables they use.  If they bundle their redundant cables together then I would say yes, it is possible that a high enough potential from a lightning jolt could induce enough potential to disable all the redundant systems on the air craft. 

The latest info in the news states that 4 minutes of telemetry indicated that the aircraft suffered depressurization. I suppose that lightning could have ruptured the pressurized cabin given the fact that the Airbus structure was not a typical aluminum skin. If the aircraft was flying into a thunderhead with an elevation of 35,000 feet who knows what wind shear or other debris the aircraft experienced. It was probably ripped apart.  Also, latest news states that route was threatened too. Who knows.

Then on a astronomical gamble, maybe it was hit by space debris....

But who knows.  From an engineering stand point I would hope that the electrical systems could withstand the lightning.  Don't know. I guess we may find out....

[Steve - WB3HUZ]

Complete with wind chimes!

I wonder what the Guiness world record is for the largest group of skydiving Irb Impersonators?

[DMOD]

From the AP

...Meteorologists said the Air France jet entered an unusual storm with 100 mph updrafts that acted as a vacuum, sucking water up from the ocean. The incredibly moist air rushed up to the plane's high altitude, where it quickly froze in minus-40 degree temperatures. The updrafts also would have created dangerous turbulence...

...With the crucial flight recorders still missing, investigators were relying heavily on the plane's automated messages to help reconstruct what happened as the jet flew through thunderstorms.

The last message from the pilot was a manual signal at 11 p.m. local time Sunday saying he was flying through an area of black, electrically charged cumulonimbus clouds that come with violent winds and lightning.

At 11:10 p.m., a cascade of problems began: the autopilot had disengaged, a key computer system switched to alternative power, and controls needed to keep the plane stable had been damaged. An alarm sounded indicating the deterioration of flight systems. Then, systems for monitoring air speed, altitude and direction failed. Controls over the main flight computer and wing spoilers failed as well. At 11:14 p.m., a final automatic message signaled loss of cabin pressure and complete electrical failure as the plane was breaking apart.

The pilot of a Spanish airliner flying nearby at the time reported seeing a bright flash of white light plunging to the ocean, said Angel del Rio, spokesman for the Spanish airline Air Comet.

The pilot of the Spanish plane, en route from Lima, Peru to Madrid, said he heard no emergency calls.

So I am sticking to the hail core and turbulent updraft theory, as hail cores in a thunderstorm can go up over 35,000 feet. I would also assume severe icing before they hit the hail core.

http://www.ucar.edu/communications/factsheets/Hail.html

http://friendfeed.com/chswx/08943754/paul-here-your-hail-core-for-you-not-most

[KA1ZGC]

I think we all agree that something in the thunderhead took the aircraft down. The only question is which something or group of somethings it was.

The more we discuss this, the more I think there was a "perfect storm" (no pun intended) of environmental conditions that destroyed the aircraft.

Lightning by itself may not be enough. Hail by itself may not be enough. Ice by itself could take the aircraft down, but doesn't explain the cascading system failures and rapid cabin depress on the way down.

Subject the aircraft to heavy windshear, moist updraft, hail, icing, and then bung a fork of lightning through the lot; then you're talking a lousy day for any aircraft. At the very least, it's a combination of conditions you can only try to test for during development without actually flying the aircraft through that kind of storm.

There may have also been some heavy convective currents (the kind that break and form tornadoes) on the leading edge of the anvil. Unless they were close enough to shore for the storm to be seen by doppler radar, we may never know.

Since investigations of this kind usually attempt to conclude with a single cause of failure, it will likely always be considered "inconclusive". As we've demonstrated to one another, it's hard to point to just one thing that could have caused all those events together.

In the meantime, the airlines may want to think twice about flying these aircraft through thunderheads. If the choice is an extra thousand gallons of fuel consumed or a cancelled flight vs. plane, passengers, and crew lost at sea; that should be a no-brainer.

[DMOD]

In the meantime, the airlines may want to think twice about flying these aircraft through thunderheads. If the choice is an extra thousand gallons of fuel consumed or a cancelled flight vs. plane, passengers, and crew lost at sea; that should be a no-brainer.

No doubt, the Airlines do seem to take more chances than usual to save a few gallons of fuel.

It appears so far a chain of events was responsible for this crash.

If the pitot tube iced up, the speed readings may not have been true either.

I think the big question is why the plane was vectored toward, or not vectored AWAY from the storm, and/or why the pilots continued through the storm?

I would love to see the results of the material tests done on the pieces; they should show any signs of explosive residue (if any) and the stresses the plane encountered.

[KA1ZGC]

I think the big question is why the plane was vectored toward, or not vectored AWAY from the storm, and/or why the pilots continued through the storm?

Well, to be fair; it's entirely possible that they were flying through a front with thunderstorms stretching for hundreds of miles along it. They probably wouldn't have had enough fuel to circumnavigate that. You can only fly through it, or turn around (if you even have enough fuel to do so).

Also, if this was a storm front they flew into, there's a very good possibility of a massive convection on its leading edge. It's basically a huge horizontal tornado stretching for hundreds of miles. If they'd flown straight into that, it would have torn them apart on the spot; but if they flew fairly close, it would be enough to cause serious structural damage.

Something certainly ripped the aircraft open prior to the crash. If explosives are ruled out (which they haven't been yet), wind and lightning are your two best choices.

This may not have been something they could fly around. Individual anvils can be circumnavigated, but a frontal boundary doesn't really leave you any choice in a trans-oceanic flight.

[KA1ZGC]

...and we can forget any conclusions we may have drawn from the wreckage. The wreckage found by the Brazilian authorities was not from this aircraft after all.

[WA1GFZ]

Bob,
Yup the wiring layout should take care of isolation and shielding quality is a big deal. Mil aircraft even consider taking a round through the harness.
I've heard a number of stories this week but the best has been updraft snapping a wing.
You should see the shielding on our fuel control wiring.

[W1VD]

Interesting info on vertical momentum from stormtrack.org:

http://www.stormtrack.org/forum/archive/index.php/t-716.html

Also, lots of pix of 'ma nature' doing her thing...check out the various participants individual websites as well...

http://www.stormtrack.org/forum/showthread.php?t=21021

[W1RKW]

I found this analysis to be of interest too.
http://www.weathergraphics.com/tim/af447/

[WU2D]

I was returning home from Switzerland and Germany on work travel in summer 2005. I had a connection out of Brussells Belgium and I was flying on an Airbus 340 heading for Boston. Anyway we could see a big storm was around the airport but we took off. We had not hit 10,000 feet yet. I would say we were just about at the point where the pilot takes his foot off the gas, maybe at 5000 feet when we got hit.

There was a bright blue blinding flash in front of my face and a crack like a 12 Gauge and the lights went out. This happened way too fast to react and nobody made a sound much less screamed. 10 seconds later the lights came back on. The engines never quit!

The pilot said in broken english (a Frankophone) - "pardon madame monseur, but we have experine de electical disturbence which is quite common"

Then we flew across the Atlantic...

Mike WU2D

[DMOD]

Not much new data on Flight 447 except that it appears that is did an uncontrolled (I assume) belly landing.

http://news.yahoo.com/s/ap/20090710/ap_on_re_la_am_ca/brazil_plane.

[flintstone mop]

I'm not very knowledgable in regards to airplanes. Why can't they fly higher. Like 50000 feet ??

Fred

[WA1GFZ]

lack of air for the motor and wings. I've seen thunder heads well above 40K on my way to Texas once.