Iceland Volcano's Ash Grounds European Air Travel 283
Ch_Omega writes "From the article at CBSNews: 'An ash-spewing volcano in Iceland emptied the skies of aircraft across much of northern Europe on Thursday, grounding planes on a scale unseen since the 9/11 terror attacks. British air space shut down, silencing the trans-Atlantic hub of Heathrow and stranding tens of thousands of passengers around the world. Aviation officials said it was not clear when it would be safe enough to fly again and said it was the first time in living memory that an ash cloud had brought one of the world's most congested airspaces to a standstill.'"
The BBC says "Safety group Eurocontrol said the problem could persist for 48 hours," and the Deccan Herald describes some of the effects on the ground in the volcano's home turf: "In Iceland, hundreds of people are fleeing rising floodwaters as the volcano under the glacier Eyjafjallajokull erupted yesterday again, for a second time in less than a month."
Re:Nothing unusual (Score:3, Informative)
Re:Nothing unusual (Score:5, Informative)
Best case scenario: some rather expensive repairs, including replacing scratched glass and engine parts(or even entire engines).
Worst case scenario: Fiery death.
Re:great name (Score:5, Informative)
It's not nearly as complicated as it seems, "fjalla" means mountain and "jokull" glacier so a native would read it more like "the glacier of the mountain Eyja" or "Eyja Mountain Glacier". But like the Scandinavian and German language they build one long word out of it.
Re:Nothing unusual (Score:4, Informative)
Not crashes, "just" 4-engine failures. All the cases I read about said once altitude was lowered the engines eventually started up again.
Having all your engines fail isn't minor, but it isn't on the same scale as an actual crash.
Re:Nothing unusual (Score:5, Informative)
The ash cloud hit my city a few hours ago (Sweden). Other than the airports closed (and I don't understand why), nothing out of ordinary is going on.
Here in England you wouldn't know anything was happening. The dust is passing over at high altitude, so its only the planes that are affected. I'm sure we'd have had a very nice sunset if it hadn't been cloudy...
Eurocontrol = Air traffic management (Score:3, Informative)
Re:Nothing unusual (Score:3, Informative)
Uhm, I think it has more to do with the jetstream, which spreads the ash cloud over Britain.
It's not intercontinental flights that are shut down. It's ALL air traffic over northwest Europe.
Re:Nothing unusual (Score:4, Informative)
This is actually untrue. Actual sand is not a problem for a modern jet engine - if you ever bothered to watch the A380 ads, one of the tests on the engine was when they fed a constant thick stream of fine sand into the intake of a running engine, and it was going just fine. It will certainly stress the engine, but it will keep running just fine for a very long time before sand starts to really wear out the internal mechanics to cause serious damage and shutdown.
Problem is that hot ash is actually not sand (which would not be able to stay that high in the air), but actual hot ash. As a result, as it goes through the engine, it coats the fuel feeding system and as it's rapidly cooled by compressed cold air pre-ignition, it becomes a glass-like material that blocks the fuel from getting into combustion chamber. This is what is causing the engine flameout. The reason why keeping the engine shut, putting plane into descent and keeping on trying to restart the engine is current modus operandi is because the glass-like substance that ash forms on the inside of the engine becomes very brittle when engine is being cooled by fast air stream going through it. As a result, when temperature drops below certain threshold, the normal vibration caused by drag and turbulence shatters the brittle mass, clearing the nozzles and allowing for fuel feeding to work again.
This is what happened in the 747 that lost all 4 of it's engines to flameout when flying through volcanic ash in the past. The report should be available to the general public, at least I recall reading it somewhere (though in finnish). In general, ash doesn't really scratch as much as stick to surfaces and solidify into dark glassy mass (which does in fact block the windows as well, meaning pilots would most likely have to land in instruments-only conditions in addition to handling engine flameouts).
Re:A tallent for understatment. (Score:3, Informative)
You know planes aren't held aloft by their engines, right? I mean, it can be hard to find an appropriate landing surface, and you certainly have less maneuvering capabilities, but a plane at 20,000' has a lot of potential energy, and a very efficient mechanism for converting that energy into stable, controllable flight.
If the wings fell off and you landed safely*, then I'd be impressed. But engines are no more necessary for safe flight than they are for safe driving -- you're better off with them, but it's hardly a death sentence to lose them.
*I am aware this has happened, and I am impressed, even if the guy was flying something more akin to a missile than a plane.
Re:great name (Score:5, Informative)
It's not nearly as complicated as it seems, "fjalla" means mountain and "jokull" glacier so a native would read it more like "the glacier of the mountain Eyja" or "Eyja Mountain Glacier". But like the Scandinavian and German language they build one long word out of it.
It is even simpler than that as Eyja means island (err, since Iceland is spelled Island in Icelandic maybe that isn't a simplification). It is a reference to the nearby Vestmann Islands, that lie just off the coast from where the glacier is.
So Eyjafjallajökull -> Islands Mountain Glacier.
Re:Nothing unusual (Score:3, Informative)
can wreck the windshield and probably the worst thing is that ash and jet engines don't get along.
I'm not sure what's worse for pilots - broken windshield when they are facing huge blow of wind or no engines.. without engines you can at least sit in the cockpit.
The reason it's getting so much attention is that there are many many flight paths that go near Iceland as it provides a shorter path between the two continents.
Actually everything around Baltic sea is currently no-flight zone. You can check out http://www.flightradar24.com/ [flightradar24.com] to see that there's only single plane over northern part of Europe.
Re:Nothing unusual (Score:3, Informative)
http://www.osha.gov/SLTC/silicacrystalline/index.html [osha.gov]
OSHA seems that exposure to silica in the crystalline form is bad stuff.
http://volcanoes.usgs.gov/ash/health/#chronic [usgs.gov]
Volcanoes, like the one in Iceland currently erupting release large amounts of the stuff.
http://en.wikipedia.org/wiki/Yellowstone_Caldera#Volcanic_hazards [wikipedia.org]
Think of the air traffic delay if Yellowstone went off!
http://en.wikipedia.org/wiki/Huckleberry_Ridge_Tuff [wikipedia.org]
Re:Nothing unusual (Score:3, Informative)
Check out the satellite imagery [nasa.gov]. The ash plume can easily reach into Europe.
It dissipates as it goes, but does anybody know the "critical density" before it's a problem?
Re:Nothing unusual (Score:3, Informative)
broken windshield when they are facing huge blow of wind
It won't break the windscreen, just sandblast it. Great for bathrooms, not so good for visual approaches.
Re:Nothing unusual (Score:1, Informative)
Re:Revenge for the Icelandic / English Bank Crisis (Score:2, Informative)
1) They weren't tax dodgers, just ordinary savers choosing to save with an Icelandic-owned bank. The British government are pissed that they compensated the savers (expecting Iceland to repay them later), and now the Icelandic government won't cough up what they owe the British government.
2) England is not the same thing as Britain, Britain is not the same thing as England. Exactly like California is not the same thing as the USA, and the USA is not the same thing as California. Not to hard to grasp, is it?
Re:Eyjafjallajokull (Score:3, Informative)
It's translated: Island - Mountain - Glacier
It's pronounced something like: Eh-ee-ah fee-at-law jeh-coot'l
Re:Nothing unusual (Score:5, Informative)
> An automobile's air filter will plug within minutes of being introduced to
> volcanic ash.
Only when there is a great deal of it: enough to impede visibility. The levels we are talking about here might cut the life of your air filter in half. Jet engines are much more sensitive to this sort of dust than internal combustion engines are. They inhale much, much, much more air, it is impossible to filter it, and they run hot enough to melt the silica.
Re:Nothing unusual (Score:3, Informative)
http://www.wolframalpha.com/input/?i=BIKF+to+EIDW [wolframalpha.com]
http://www.wolframalpha.com/input/?i=BIKF+to+ENGM [wolframalpha.com]
http://www.wolframalpha.com/input/?i=BIKF+to+EKCH [wolframalpha.com]
Katla Volcano (Score:5, Informative)
There is another, larger, volcano nearby called Katla and ...
"Eyjafjallajokull has blown three times in the past thousand years," Dr McGarvie told The Times [timesonline.co.uk], "in 920AD, in 1612 and between 1821 and 1823. Each time it set off Katla." The likelihood of Katla blowing could become clear "in a few weeks or a few months", he said.
Given this, and given that the last eruption was on and off for 2 years, we could have travel interruptions for a while to come.
The next Iceland volcano is much bigger (Score:5, Informative)
Map failure (Score:3, Informative)
I noticed a few people up above slightly confused about where Iceland is, based on misleading map projections. But WCBS radio (New York) this morning certainly gets the fail-prize for World Geography; their commentator noted how a volcano erupting "halfway around the world" was canceling flights from New York to London.
Nice going, guys. All the Londoners stuck in the airport who were listening now have an even worse opinion of American geographical knolwegde.
Re:A tallent for understatment. (Score:2, Informative)
To add some numbers to your argument:
The given glide ratio of a 747 is 15:1. For every one foot you drop, you move forward 15. This is under IDEAL conditions. So, considering that commercial flights occur between 30,000 to 38,000 feet (mid-flight), that means that an unpowered 747 would have 85.2 to 102 miles of forward range before hitting the ground. Now consider the unlikely case that the 747 has an airport or suitable landing area directly in front of them and lined up and some things become obvious.
Even if you're at maximum altitude when you're 747 loses its propulsion, you.... are.... screwed... 85 to 102 miles is very little range. Add to that the fact that the plane will almost certainly need to turn to present an acceptable landing arrangement, significantly harming the glide ratio during the turn, and you end up with something very close to a nightmare scenario.
If you've never seen video of a jokulhlaup (Score:1, Informative)
You should check out the videos of the example in progress at Eyjafjallajökull [youtube.com]. It's *awesome*. And if you don't know what a jökulhlaup [wikipedia.org] is, it's a huge meltwater flood that is generated by the heat of the volcanic eruption melting the ice beneath a glacier. Eventually the reservoir of water bursts out from beneath the glacier.
Nice maps of the current and earlier Iceland eruption in March can be found at the Nordic Volcanological Center [norvol.hi.is].
Re:great name (Score:3, Informative)