4 ms·

How airplanes counteract St. Elmo's Fire during thunderstorms

40 points by lelf 6y ago

bediger4000 6y ago
TL;DR: they squirt "St Elmo's water" on it.
- dang 6y ago
  Please don't do this here.
supernova87a 6y ago
The article is a little thin on the finding being useful to do something with it. Because if what they describe is the case, then planes flying around have been self-protecting against coronal discharge already.
jandrese 6y ago
The answer is: By going fast.
- mmmpetrichor 6y ago
  And not touching the ground! :)
- anonytrary 6y ago
  The answer is: By being a hollow conductor.
harrydehal 6y ago
Great article. It's funny to me that, after decades of presumably a decently well-read academic life, I'm finally able to put into context the actual meaning of "St. Elmo's Fire." I had only been tangentially aware of the pop culture references in music (e.g. Brian Eno https://www.youtube.com/watch?v=AZKch8dZ61w https://www.youtube.com/watch?v=AZKch8dZ61w) and film (I have not seen the film with Emilio Estevez, Rob Lowe, and Demi Moore, although it looks interesting, e.g. https://www.imdb.com/title/tt0090060/ https://www.imdb.com/title/tt0090060/) Here's more reading on the actual Erasmus of Formia, or St. Elmo: https://en.wikipedia.org/wiki/Erasmus_of_Formia https://en.wikipedia.org/wiki/Erasmus_of_Formia
- psim1 6y ago
  The film is the origin of the “brat pack” and the John Parr/David Foster song that the lite FM stations play every other day.
User23 6y ago
I was on a plane that was struck by lightning once. It sounded like a bomb had just gone off. For about 10 seconds nobody on the plane made a sound as we all tried to figure out if we were screwed or not. After a couple minutes the captain came on doing his best Chuck Yeager impression, as is tradition, and explained to us what had happened and that there was really no reason to worry because it happens all the time and the planes are designed for it.
- VBprogrammer 6y ago
  It's actually getting more and more of a problem with the amount of composites going into modern airliners. They have to build in elaborate foils and meshes to conduct any discharge around the airframe.
  - _-___________-_ 6y ago
    "more and more of a problem" is maybe a bit dramatic. It's a design constraint of composite structures exposed to lightning that you need to provide electrical pathways, which is what the designers do, and composite aircraft regularly get struck by lightning with no damage caused.
    - VBprogrammer 6y ago
      I don't think it's particularly dramatic. The Boeing 787 is the first airliner to really use composites to a high degree in its structure. There was and is plenty of controversy around it's lightening protection design. For example https://www.seattletimes.com/business/boeing-aerospace/faa-engineers-objected-to-boeings-removal-of-some-787-lightning-protection-measures/ https://www.seattletimes.com/business/boeing-aerospace/faa-e... It's also been controversial in small aircraft like the Cirrus SR22, for example complete failure of the radios and / or electric systems due to static buildup on the airframe. I'd say it's far from a solved problem.
      - _-___________-_ 6y ago
        It is literally a solved problem at this point. You solve it by providing electrical pathways within the structure, which is what is done in the 787 and other composite-hulled aircraft, and these aircraft regularly get struck by lightning with no issues. I am not deeply familiar with the SR22, but if they are having those issues I guess they didn't implement the well-known solutions, or didn't implement them properly.
growlist 6y ago
Isn't it strange. I was just reading about St Elmo's Fire last night after watching a documentary about Air France Flight 447, and now today this.
- Loughla 6y ago
  I know it's all random chance, but I like to think that when that sort of thing happens, it is legitimately the universe telling me something. Maybe you're going to be hit by lightning?
  - growlist 6y ago
    I'm guessing you didn't like my comment on your post yesterday (https://news.ycombinator.com/item?id=24124248 https://news.ycombinator.com/item?id=24124248), and stalked me looking for an opportunity to hit back? Bit scary. Was it mention of Soros that you took exception to?
    - Loughla 6y ago
      Oh, man. No. The lightning thing was 100% meant as a joke, and that I made a comment your posted to yesterday is 10000% coincidence. I don't even look at usernames on here. Your post on that didn't really have anything to do with what I was saying originally, wasn't really negative to elicit a response, and genuinely didn't even register on my radar until you linked to it just here. Relax. What a weird coincidence.
      - growlist 6y ago
        Spooky.
- Brajeshwar 6y ago
  Absolutely. When I was doing Hydroponics/Aeroponics, I keep seeing all of those pretty much everywhere. That didn't work out so I'm now on to Satellite Imagery for Agriculture and I see that everywhere. The world works its own stories but directed for you.

40 points by lelf 6y ago

bediger4000 6y ago

TL;DR: they squirt "St Elmo's water" on it.

dang 6y ago
Please don't do this here.

supernova87a 6y ago

The article is a little thin on the finding being useful to do something with it. Because if what they describe is the case, then planes flying around have been self-protecting against coronal discharge already.

jandrese 6y ago

The answer is: By going fast.

mmmpetrichor 6y ago
And not touching the ground! :)
anonytrary 6y ago
The answer is: By being a hollow conductor.

harrydehal 6y ago

Great article. It's funny to me that, after decades of presumably a decently well-read academic life, I'm finally able to put into context the actual meaning of "St. Elmo's Fire." I had only been tangentially aware of the pop culture references in music (e.g. Brian Eno https://www.youtube.com/watch?v=AZKch8dZ61w https://www.youtube.com/watch?v=AZKch8dZ61w) and film (I have not seen the film with Emilio Estevez, Rob Lowe, and Demi Moore, although it looks interesting, e.g. https://www.imdb.com/title/tt0090060/ https://www.imdb.com/title/tt0090060/) Here's more reading on the actual Erasmus of Formia, or St. Elmo: https://en.wikipedia.org/wiki/Erasmus_of_Formia https://en.wikipedia.org/wiki/Erasmus_of_Formia

psim1 6y ago
The film is the origin of the “brat pack” and the John Parr/David Foster song that the lite FM stations play every other day.

User23 6y ago

I was on a plane that was struck by lightning once. It sounded like a bomb had just gone off. For about 10 seconds nobody on the plane made a sound as we all tried to figure out if we were screwed or not. After a couple minutes the captain came on doing his best Chuck Yeager impression, as is tradition, and explained to us what had happened and that there was really no reason to worry because it happens all the time and the planes are designed for it.

VBprogrammer 6y ago
It's actually getting more and more of a problem with the amount of composites going into modern airliners. They have to build in elaborate foils and meshes to conduct any discharge around the airframe.
- _-___________-_ 6y ago
  "more and more of a problem" is maybe a bit dramatic. It's a design constraint of composite structures exposed to lightning that you need to provide electrical pathways, which is what the designers do, and composite aircraft regularly get struck by lightning with no damage caused.
  - VBprogrammer 6y ago
    I don't think it's particularly dramatic. The Boeing 787 is the first airliner to really use composites to a high degree in its structure. There was and is plenty of controversy around it's lightening protection design. For example https://www.seattletimes.com/business/boeing-aerospace/faa-engineers-objected-to-boeings-removal-of-some-787-lightning-protection-measures/ https://www.seattletimes.com/business/boeing-aerospace/faa-e... It's also been controversial in small aircraft like the Cirrus SR22, for example complete failure of the radios and / or electric systems due to static buildup on the airframe. I'd say it's far from a solved problem.
    - _-___________-_ 6y ago
      It is literally a solved problem at this point. You solve it by providing electrical pathways within the structure, which is what is done in the 787 and other composite-hulled aircraft, and these aircraft regularly get struck by lightning with no issues. I am not deeply familiar with the SR22, but if they are having those issues I guess they didn't implement the well-known solutions, or didn't implement them properly.

growlist 6y ago

Isn't it strange. I was just reading about St Elmo's Fire last night after watching a documentary about Air France Flight 447, and now today this.

Loughla 6y ago
I know it's all random chance, but I like to think that when that sort of thing happens, it is legitimately the universe telling me something. Maybe you're going to be hit by lightning?
- growlist 6y ago
  I'm guessing you didn't like my comment on your post yesterday (https://news.ycombinator.com/item?id=24124248 https://news.ycombinator.com/item?id=24124248), and stalked me looking for an opportunity to hit back? Bit scary. Was it mention of Soros that you took exception to?
  - Loughla 6y ago
    Oh, man. No. The lightning thing was 100% meant as a joke, and that I made a comment your posted to yesterday is 10000% coincidence. I don't even look at usernames on here. Your post on that didn't really have anything to do with what I was saying originally, wasn't really negative to elicit a response, and genuinely didn't even register on my radar until you linked to it just here. Relax. What a weird coincidence.
    - growlist 6y ago
      Spooky.
Brajeshwar 6y ago
Absolutely. When I was doing Hydroponics/Aeroponics, I keep seeing all of those pretty much everywhere. That didn't work out so I'm now on to Satellite Imagery for Agriculture and I see that everywhere. The world works its own stories but directed for you.