LH3431 B737 lightning strike?
Join Date: Aug 2007
Location: Bournemouth, UK
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Video of a Strike
The video of the Nippon 747 getting struck on climb out has no doubt been seen by most.... but how about this strike on a Qantas 767:
http://www.youtube.com/watch?v=036hpBvjoQw
http://www.youtube.com/watch?v=036hpBvjoQw
Join Date: Jan 2008
Location: Sonoma, CA, USA
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Re: Lightning and CBs
In my post above, I referred to a strike in a Beech D-18. This happened in the
San Joachin Valley in California around 2:30AM local on a mail flight. The air was very clear under a few scattered clouds. There was no rain or turbulence. We could see lightning in the distance. It was what we in California call dry lightning.
Suddenly there was a blinding flash and then nothing electrical worked. It took a good 2 -3 minutes to get our night vision back. We were near our destination of Fresno. The tower was closed for the night so we just landed, offloaded the mail and slept until we could find someone to fix the machine.
San Joachin Valley in California around 2:30AM local on a mail flight. The air was very clear under a few scattered clouds. There was no rain or turbulence. We could see lightning in the distance. It was what we in California call dry lightning.
Suddenly there was a blinding flash and then nothing electrical worked. It took a good 2 -3 minutes to get our night vision back. We were near our destination of Fresno. The tower was closed for the night so we just landed, offloaded the mail and slept until we could find someone to fix the machine.
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Rain is often quite electrically charged. I noticed this several years ago when I had a long wire antenna strung down the garden. It was raining and I could hear an irregular 'tick....tick' It turned out to be the antenna sparking across the metal plates of a tuning capacitor to ground. What's more, it can change polarity, as I discovered when I connected a neon bulb between the antenna and ground - at the start of the shower one electrode was glowing, by the end, the other one was. I guess it's not beyond the bounds of probability that an aircraft could collect a significant charge and then fly into a cloud of opposite polarity. Whether it would quietly discharge or whether you'd get a sudden lightning type discharge I don't know. It may be that the dissipaters on the trailing edges would stop it ever getting to that stage.
The action of the leading edges slicing through the air can knock electrons off of atoms to create ions (in the same way that it happens with the water molecules), so if there's enough potential around, the mere passage of an aircraft can actually cause lightning even if otherwise it might not have happened. There was a North Sea helicopter that took a strike to the tail rotor (and subsequently ditched) that was attributed to this mechanism.
The action of the leading edges slicing through the air can knock electrons off of atoms to create ions (in the same way that it happens with the water molecules), so if there's enough potential around, the mere passage of an aircraft can actually cause lightning even if otherwise it might not have happened. There was a North Sea helicopter that took a strike to the tail rotor (and subsequently ditched) that was attributed to this mechanism.
Join Date: Dec 2001
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> All the fibres of the shaggy garment were sticking out - standing on end.
> Something to do with the raindrops making contact with me. I was in
> Wellys, so I would have been insulated from the ground.
Not too hard to explain. The -ve electric charge on the underside of the cloud causes +ve charge to accumulate in the ground and on objects under the cloud (eg your head). This is because opposite charges attract and alike repel. Your feet would have been -ve if insulated from the ground. These +ve charges are attracted to the cloud and repelled by each other causing hair and fiber to be pulled up and out.
There are several demos on Youtube using a Van de Graaf generator to produce the high voltages needed...
http://www.youtube.com/watch?v=2rSYc...eature=related
http://www.youtube.com/watch?v=46tju...eature=related
One with an explanation..
http://www.youtube.com/watch?v=Ah2DuXGzGGc
> Something to do with the raindrops making contact with me. I was in
> Wellys, so I would have been insulated from the ground.
Not too hard to explain. The -ve electric charge on the underside of the cloud causes +ve charge to accumulate in the ground and on objects under the cloud (eg your head). This is because opposite charges attract and alike repel. Your feet would have been -ve if insulated from the ground. These +ve charges are attracted to the cloud and repelled by each other causing hair and fiber to be pulled up and out.
There are several demos on Youtube using a Van de Graaf generator to produce the high voltages needed...
http://www.youtube.com/watch?v=2rSYc...eature=related
http://www.youtube.com/watch?v=46tju...eature=related
One with an explanation..
http://www.youtube.com/watch?v=Ah2DuXGzGGc
Join Date: Feb 2006
Location: Germany, South-East Bavaria (Oberbayern)
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The "aviate, navigate, communicate" principle has already been mentioned and one might add that Sofia is surrounded by high hills with a 7500 ft peak immediately south of the field. I've been there many times and remember this airport as extremely terrain critical; you really want to know what you're doing even under the best of conditions.
I'd hate to be in that basin with thunderstorms all over the place and an airplane "trying to shake its tail loose", as somebody put it. I imagine stress levels skyrocketed for the crew and they were extremely busy with the "aviate" and "navigate" parts. Add to that an ATC environment with lots of room for improvement, and you get a situation where they probably did not have any capacity left to tell the passengers what was going on.
Anyway, they did a great job in putting it down safely and deserve to be saluted for it.
I'd hate to be in that basin with thunderstorms all over the place and an airplane "trying to shake its tail loose", as somebody put it. I imagine stress levels skyrocketed for the crew and they were extremely busy with the "aviate" and "navigate" parts. Add to that an ATC environment with lots of room for improvement, and you get a situation where they probably did not have any capacity left to tell the passengers what was going on.
Anyway, they did a great job in putting it down safely and deserve to be saluted for it.
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Tnx!
Tnx again for all great answers. It was a very good "recovery" for me first to get all the physical "evidence" . I now know extremly much more of what happened, why and what could happen. I surely understand the situation the pilots was in and I never thought that they didnt do the best. We met the pilot at the hotel and I am sure that if he had the time he would have communicated better. All honours to them getting the plain down as safely and smooth as it went.
As for the phsycical situation I am now feeling much better. The worst was the thoughts af the panic situation and the thoughts that went through my head about my family. We had a debriefing at our company that helped a lot, and I know can say that I am 99,9 % recovered
Actually I am travelling to Vienna on thursday, and it is difficult to go there with another transport than a plane...
I guess that I probably will be a bit more tenced, but I think I will have no problems flying again.
Again....a lot of thanks for all the answers
As for the phsycical situation I am now feeling much better. The worst was the thoughts af the panic situation and the thoughts that went through my head about my family. We had a debriefing at our company that helped a lot, and I know can say that I am 99,9 % recovered
Actually I am travelling to Vienna on thursday, and it is difficult to go there with another transport than a plane...
I guess that I probably will be a bit more tenced, but I think I will have no problems flying again.
Again....a lot of thanks for all the answers
