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Iceland Volcano's Ash Grounds European Air Travel
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."
As watching endless episodes of Discovery channel would tell you ash has been responsible for plane crashes in the past. http://en.wikipedia.org/wiki/British_Airways_Flight_9
My cat can type words like Eyjafjallajokull too.
The last eruption was in 1821 and lasted 2 years... you better get yourself some train tickets if you want to travel in Europe!
The trouble with ash and aircraft is that, at the high temperatures found in jet engine combustion chambers, ash turns into a delightful material extremely similar to molten glass(you also have the less immediately dramatic; but still annoying, problem of having the ash particles basically sandblasting the surface of the aircraft).
Best case scenario: some rather expensive repairs, including replacing scratched glass and engine parts(or even entire engines).
Worst case scenario: Fiery death.
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...
In a survey of 100 programmers, 111111 thought that duck-typing was a good idea.
England and Iceland have been in a huff ever since a lot of English tax dodgers lost their fortunes in Icelandic banks that went tits up. The British have been threatening Iceland with everything, even including their major satire weapon weapon of mass destruction, "Viz" ( http://en.wikipedia.org/wiki/Viz )
The Icelandians have responded with volcanic gas.
Let's hope that this situation doesn't escalate.
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
They closed the airports because the ash eats up jet engines, and can't easily be detected on radar. It's mostly silica and doesn't have a dielectric constant different enough from air to show up on most aircraft radar. So even if the cloud is thin enough on the ground to take off safely, you are relying on visual indications of the clouds thickening, and your visibility is poor so it's hard to see.
Any pissed off European travelers stuck in the airport reading /. may want to read KLM vs. Mt. Reboubt before hitting the friendly skies.
First they fucked up our fishing, then they fucked up our economy, now they're fucking up our air. I say we INVADE these unpronounceable herring-botherers.
Well, I just had a beer with my little brother, a BA Pilot grounded here at our home in switzerland.
BA Flight 009 was special because it is the first such incident documented in a modern jet airliner. The pilots were pretty clouless when they suddenly saw funny flares through their front windows (cause by ash particles). "Somke" was reported from the cabin and after some time they piloted a very expensive glider plane (all 4 engines failed). The 747 has a glide angle of something about 1:15 which is very good for a heavy airliner. But with failing speed indicators it is quiet a challange to restart engines midair (windmill effect is used, they need to hold a certain speed before they can inject fuel and ignite it again).
I think these pilots back then did a tremendously good job if one takes into account that they had no fucking clue what was going on (today they have procedures for such situations, my brother showed me his checklist for such cases). And they had a lot of luck. The pilots lost height due to engine failure, decided to do a 180 turn and once the engines restarted (pretty low) they got into the ash cloud again and lost some engines again before they landed with reduced sight (sandpaper effect on the front window) and reduced IFR instrumentation at night.
Cheers,
-S
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).
ALING, Heathrow, Thursday (NTN) — Prime Minister Gordon Brown has condemned Iceland's terrorist attack on British air travel and their refusal to refund tourists' air tickets.
The UK government used anti-terrorism laws to freeze all British-held assets of Umhverfisráðuneyti, the Icelandic Ministry Against the Environment, after minister Kolbrún Halldórsdóttir threatened to further unleash the power of the Katla volcano in the wake of the devastation to school holidays caused by Eyjafjallajökull.
Thousands of confused and angry passengers wandered around Britain's becalmed airports today trying in vain to find out how long the disruption caused by the ash cloud might last. "Can't we just, you know, give the planes a try?" said Brenda Busybody, 54 (IQ), of East Cheam. "I wanted to go and rest on holiday, and Monday I'm back to doing nothing in the office. I pay my licence fee!"
The Prime Minister offered his outrage and sympathy, in lieu of money or anything useful. "This is fundamentally a problem with the Icelandic-registered El-stodth Thyonustah Voweld," said Mr Brown, attempting not to choke on his own tongue. "They have failed the people of Iceland and they have failed the people of Northern Europe! You pay my licence fee! Er, hold on ..."
Icelandic Prime Minister Jóhanna Sigurðardóttir also offered her sympathies to British travellers. "But, you know, we're still pretty upset about the cod."
http://rocknerd.co.uk
Which isn't what the parent said. Did you just want to wheel out your A380 advert anecdote? :) The parent said hot ash turning into molten glass-like substance is a problem for engines. Which you disagreed with, then repeated!
> 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.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
As Flight 9 approached Jakarta, the crew found it difficult to see anything through the windscreen, and had to make the approach almost entirely on instruments [...] He then called out how high they should be at each DME step along the final track to the runway, creating a virtual glide slope for them to follow. It was, in Moody's words, "a bit like negotiating one's way up a badger's arse".
British Airways pilots, always classy.
There is another, larger, volcano nearby called Katla and ...
"Eyjafjallajokull has blown three times in the past thousand years," Dr McGarvie told The Times, "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.
When this Iceland volcano erupts, nearby Katla always goes up soon after. A major eruption of Katla could give us another "Year without a summer" in the northern hemisphere.
Help stamp out iliturcy.
Ah yes, the icelandic trout. Most modern airliners now have somke detectors for just such problems.