Saving Ash from a Volcanic Eruption: A Geologist's Perspective

[ViewsofMars]

"

You don't fly air-breathing engines in ash, period.

@ViewsofMars: *shrug*

"

Duh, FrameDragger! You don't fly airplane(s) into air space that has volcanic ash. You can locate that information in several articles via link that I have provided on this page and the previous one.
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"

Haven't heard of protests, but the pilots who made http://www.cnn.com/2010/TRAVEL/04/18/volcano.ash.test.flights/index.html?hpt=T1" must not have felt they were in danger, otherwise they would not have flown. The test flights, btw, apparently showed no ill effects from the concentrations of ash through which they flew (which I presume were quite low).

I think it's a good bet that there is a concentration of ash which is safe to fly through; what that level is isn't known. Which raises the question: is there a way to measure concentration of airborne ash? Because before we can determine what level is safe to fly through, we need a way to measure it.

"

Hi lisab. :) Since pilots are inside the plane, I doubt there would be volcanic ash in the air they breathe. Volcanic ash clogs up the engine of a plane. Perhaps a very short span of time in air space with ash might not cause a plane's engine to die. Of course, measuring what level is safe could result in the pilot's death. Of course, they would have to get an *ok* by the control center of an airport and present the route. Has that happened yet?

Quite frankly, I haven't located the instrument used for measuring in air space the amount of volcanic ash. Perhaps, we should go digging for that information. I'm sure it's out there in cyberspace.
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"

@ViewsofMars: "Duh"? I don't know if you're angry or amused, but you're absolutely making me laugh in real life (with, not at). Maybe a bit of a softer touch would be helpful however? Everyone doesn't feel as rough-and-tumble online as I do.

"

FrameDragger, I'm a serious contender with a gentle manner. And I don't mind you
rolling on the floor laughing. Also, as you can see, I like to condense cyberspace and free it up for others. I personally think a person should enjoy particpating in discussions. I may not always agree with everything someone has to say, but I do appreciate knowing that people are having a wee bit of fun.

 

[Frame Dragger]

Haven't heard of protests, but the pilots who made http://www.cnn.com/2010/TRAVEL/04/18/volcano.ash.test.flights/index.html?hpt=T1" must not have felt they were in danger, otherwise they would not have flown. The test flights, btw, apparently showed no ill effects from the concentrations of ash through which they flew (which I presume were quite low).

I think it's a good bet that there is a concentration of ash which is safe to fly through; what that level is isn't known. Which raises the question: is there a way to measure concentration of airborne ash? Because before we can determine what level is safe to fly through, we need a way to measure it.

Sure, you could probably do these tests at JPL...I believe they had a setup to test the effect of static discharge caused by particulate matter.

The problem is: Volcanic ash is not homogenous, and just hasn't been well studied. It takes some time for glass to choke an engine, and frankly... who will take that risk with a full cabin? There is the issue I raised earlier as well, which is that there could be cumulative damage.

I would also add that pilots do things such as fly into Hurricanes, not because they feel they are in no danger, but for the same reasons they fly into Anti Aircraft Fire. They have to: it's a job they love, and there is no other way right now (that people are willing to pay for). I doubt those same pilots would do this with a 747 and a full crew-cabin.

Finally, what is a safe concentration? You could determine an average, and still run into a sticky patch, which probably means that you and all souls will be lost. Airplanes just don't have much of a fail-safe at high altitudes if the engines are glassed.

@ViewsofMars: "Duh"? I don't know if you're angry or amused, but you're absolutely making me laugh in real life (with, not at). Maybe a bit of a softer touch would be helpful however? Everyone doesn't feel as rough-and-tumble online as I do.

 

[Borek]

I recall a NatGeo or Discovery program which described a plane that had flown into volcanic ash. The pilots had no CLUE what was happening, other than intermittant engine failure. They finally figured out that it was the ash vitrifying in the engines, but only once they landed. The pilots were simply bright and lucky enough to realize that they couldn't fly at their normal cruising altitude.

http://en.wikipedia.org/wiki/British_Airways_Flight_9

 

[Frame Dragger]

http://en.wikipedia.org/wiki/British_Airways_Flight_9

Borek you wigged genius, THANK you!

 

[lisab]

Sure, you could probably do these tests at JPL...I believe they had a setup to test the effect of static discharge caused by particulate matter.

The problem is: Volcanic ash is not homogenous, and just hasn't been well studied. It takes some time for glass to choke an engine, and frankly... who will take that risk with a full cabin? There is the issue I raised earlier as well, which is that there could be cumulative damage.

I would also add that pilots do things such as fly into Hurricanes, not because they feel they are in no danger, but for the same reasons they fly into Anti Aircraft Fire. They have to: it's a job they love, and there is no other way right now (that people are willing to pay for). I doubt those same pilots would do this with a 747 and a full crew-cabin.

Finally, what is a safe concentration? You could determine an average, and still run into a sticky patch, which probably means that you and all souls will be lost. Airplanes just don't have much of a fail-safe at high altitudes if the engines are glassed.

@ViewsofMars: "Duh"? I don't know if you're angry or amused, but you're absolutely making me laugh in real life (with, not at). Maybe a bit of a softer touch would be helpful however? Everyone doesn't feel as rough-and-tumble online as I do.

Yes, good points. I would expect the ash concentration to vary some, but I wonder how much the ash itself varies? Are some types of ash more likely to glassify than others? I really don't know.

 

[Galteeth]

Is this eruption likely to have any short term effects on the climate?

 

[Frame Dragger]

Yes, good points. I would expect the ash concentration to vary some, but I wonder how much the ash itself varies? Are some types of ash more likely to glassify than others? I really don't know.

The answer is "yes". Some ash is organic or composed of non-silicates, but a LOT of it is very fine pumice, which vitrifies like *snaps fingers*. There is also glass ALREADY suspended in the ash, which rapidly melt and then fuse, forming nucelation sites for more growth.

This might be useful: http://volcanoes.usgs.gov/ash/properties.html

 

[Frame Dragger]

Is this eruption likely to have any short term effects on the climate?

The ash is unlikely to have much of an effect, but if this volcano released a lot of SOx, then it could have an effect for 2 or 3 years.

 

[tomkeus]

http://en.wikipedia.org/wiki/British_Airways_Flight_9

I'm really getting tired of people quoting BA Flight 9. It went into ash plume 150km downwind of the volcano. I don't see that this case is any argument to close down airspace 2000 or 3000km away from the Iceland.

Even after that, Indonesian authorities have closed down just the area adjacent to the volcano. They didn't proceed and shut down entire South East Asia.

I mean, we had large eruptions, even larger recently but not one caused shutdown on such large scale as in Europe. This is plain and simple irrational paranoia.

For example, engine flameouts did occur while flying through heavy rains. Does this mean we have to ground all air traffic if we have some rain sipping somewhere?

 

[ViewsofMars]

"

The problem is: Volcanic ash is not homogenous, and just hasn't been well studied. It takes some time for glass to choke an engine, and frankly... who will take that risk with a full cabin? There is the issue I raised earlier as well, which is that there could be cumulative damage.

"

Frame Dragger, do you have a link (url) to substantiate your claim?

"

I would also add that pilots do things such as fly into Hurricanes, not because they feel they are in no danger, but for the same reasons they fly into Anti Aircraft Fire. They have to: it's a job they love, and there is no other way right now (that people are willing to pay for). I doubt those same pilots would do this with a 747 and a full crew-cabin.

"

Frame Dragger, do you have a link (url) to substantiate your claim?

"

Finally, what is a safe concentration? You could determine an average, and still run into a sticky patch, which probably means that you and all souls will be lost. Airplanes just don't have much of a fail-safe at high altitudes if the engines are glassed.

"

Frame Dragger, do you have a link (url) to substantiate your claim?

FrameDragger, I'm strickly asking for references for my own on-line library collection. (Please note that I have on the last two previous pages to this topic provided links (url's).) Thanks in advance for your help FrameDragger.

 

[Frame Dragger]

""

Frame Dragger, do you have a link (url) to substantiate your claim?

""

Frame Dragger, do you have a link (url) to substantiate your claim?

""

Frame Dragger, do you have a link (url) to substantiate your claim?

FrameDragger, I'm strickly asking for references for my own on-line library collection. (Please note that I have on the last two previous pages to this topic provided links (url's).) Thanks in advance for your help FrameDragger.

Please don't take this the wrong way, but this is something you can do with google and search terms such as "hurricane flight plane" or "composition volcanic ash". From there, you whittle down the info to something more specific, such as: "Volcanic ash troposphere remain" or "concentrations". Here is a simple search: "Composition volcanic ash"... and look at what it yields: http://www.google.com/search?hl=en&rlz=1T4DKUS_enUS306US306&q=composition+volcanic+ash&aq=f&aqi=g-m1&aql=&oq=&gs_rfai=

When it comes to something like QM or Relativity, I can understand wanting citations, but in this case it's probably good to do independant research, if for no better reason than having that skill at hand.

@tomkeus: Good luck selling that to your insurance company and investors if you own an airline.

 

[mheslep]

About aircraft range and altitude. Maybe this http://selair.selkirk.ca/Training/Aerodynamics/range_jet.htm helps a bit, especially this sixth graph.

Notice that a fuel flow of 540 lbs/hr generates a max range speed of 200 knots true airspeed (KTAS) at sea level and 440 KTAS at 45,000 feet. Notice also that the sea level curve is much steeper, so flying faster than best range is at a greater penalty than at high altitude.

Also I expect this graph to be based on air density only since -as said- the temperature and related mach number play a big role for engine performance/efficiency and these are not linear in that altutide range due to the tropopause.

The exact numbers are not very relevant but it gives an impression of the rate of changes in range versus altitude.

I was generally aware of these penalties, and they suggest to me a reason for temporarily raising the ticket prices to pay for more fuel and for reducing the number of flights. It doesn't explain to me, by itself, why the airspace should be completely shut down.

 

[ViewsofMars]

Please don't take this the wrong way, but this is something you can do with google and search terms such as "hurricane flight plane" or "composition volcanic ash". From there, you whittle down the info to something more specific, such as: "Volcanic ash troposphere remain" or "concentrations". Here is a simple search: "Composition volcanic ash"... and look at what it yields: http://www.google.com/search?hl=en&rlz=1T4DKUS_enUS306US306&q=composition+volcanic+ash&aq=f&aqi=g-m1&aql=&oq=&gs_rfai=

Why would I use Google? I am a science researcher. I go to either peer-reviewed articles or use U.S. Government-Science website for scientific information, or a scientist's website, etc. By the way, I already had reviewed http://volcanoes.usgs.gov/ash/properties.html
I was basically asking you for a website to confirm your comments. Please don't through it back on me. Why? Because it is insulting. I'm especially still waiting on your comment, "Finally, what is a safe concentration? You could determine an average, and still run into a sticky patch, which probably means that you and all souls will be lost. Airplanes just don't have much of a fail-safe at high altitudes if the engines are glassed." That isn't a scientific statement.

 

[tomkeus]

@tomkeus: Good luck selling that to your insurance company and investors if you own an airline.

You don't have to sell anything. Just wait for a few more days for losses to accumulate and they will be begging you get those planes airborne.

 

[sophiecentaur]

About aircraft range and altitude. Maybe this http://selair.selkirk.ca/Training/Aerodynamics/range_jet.htm helps a bit, especially this sixth graph.

[PLAIN]http://selair.selkirk.ca/Training/Aerodynamics/graphics/altitude-jet1.gif

Notice that a fuel flow of 540 lbs/hr generates a max range speed of 200 knots true airspeed (KTAS) at sea level and 440 KTAS at 45,000 feet. Notice also that the sea level curve is much steeper, so flying faster than best range is at a greater penalty than at high altitude.

Also I expect this graph to be based on air density only since -as said- the temperature and related mach number play a big role for engine performance/efficiency and these are not linear in that altutide range due to the tropopause.

The exact numbers are not very relevant but it gives an impression of the rate of changes in range versus altitude.

Thanks for the info on those graphs Andre. Looking at the minima on those two red curves it seems to me that the 'fuel consumption' (mpg, in motorcar terms, ignoring winds) at 45k is about twice that at sea level. (i.e. same fuel flow at just over twice the air speed) Presumably it wouldn't be quite so bad at 10k as at ground level. That would imply that the cost of flying low would only be about twice that of flying at normal altitudes. Sounds a lot more attractive than spending hundreds of pounds on hire cars, extended stays in hotels and missed business deals.

So why aren't they considering at least some flights (high priority, perhaps) at lower, safe, altitudes? Is it just an admin (ATC) problem?

I feel that this thread should be split into two - one to deal with the safety issue and the other to discuss possible (non-hazardous) solutions.

 

[Frame Dragger]

I was basically asking you for a website to confirm your comments. Please don't through it back on me. Why? Because it is insulting.

It is responding with the understanding that you were being rude, and patronizing, and apparently unwilling to perform your own research to confirm a statement. In short, returning your "offer" is no more insulting than it was for you to make the request in the first place. You were hardly being subtle, polite, or reasonable. I on the other hand, gave you the benefit of the doubt, a mistake I won't make twice. As for you being a "science researcher", that statement alone gives away a great deal about what you are, and are not. If you have a further issue, feel free to continue, but my new policy on PF is to disengage and report now. Keep that in mind.

 

[Frame Dragger]

You don't have to sell anything. Just wait for a few more days for losses to accumulate and they will be begging you get those planes airborne.

No, they won't. Those losses won't be fatal for a business, but a crash that could be blamed on negligence (can you IMAGINE the civil trials alone?!) could absolutely ruin an airline. A plane that crashes now is immediately going to do ENORMOUS damage to a company's public image, and as Pan AM could have told you, that matters when you're trying to convince people to fly in your aluminum and composite cigar with wings.

EDIT: On the bright side, we just wait those few days and see who is correct. No need for speculation when time will answer this.

 

[ViewsofMars]

It is responding with the understanding that you were being rude, and patronizing, and apparently unwilling to perform your own research to confirm a statement.

Frame Dragger, that is your opinion.

In short, returning your "offer" is no more insulting than it was for you to make the request in the first place. You were hardly being subtle, polite, or reasonable. I on the other hand, gave you the benefit of the doubt, a mistake I won't make twice. As for you being a "science researcher", that statement alone gives away a great deal about what you are, and are not. If you have a further issue, feel free to continue, but my new policy on PF is to disengage and report now. Keep that in mind.

Frame Dragger, that again is your opinion. I think you are skating around to basically avoid answering that last question of mine to you! Which is absolutely not a scientific answer. Retraction from you is never an option as I can see. Furthermore, the language you have used isn't scientific by any means.

 

[Frame Dragger]

Frame Dragger, that is your opinion.




Frame Dragger, that again is your opinion, which is absolutely worthless. I think you are skating around to basically avoid answering that last question of mine to you! Which is absolutely not a scientific answer. Retraction from you is never an option as I can see. Furthermore, the language you have used isn't scientific by any means.

Again, you're rude, patronizing, and making vast assumptions which reveal your intial bias. You're simply not being subtle enough that anyone would miss that either, and frankly, why would anyone BOTHER to reply to you? This is my last reply in this conversation (regarding you), which you are more than welcome to see as a personal victory. I could care less.

EDIT: You know what, even a rabid dog deserves a bone. Here: "Colonel Joseph Duckworth (USAF)". Enjoy learning about how and why people fly into hurricanes. The rest, I leave in your "sceince researcher" hands.

 

[tomkeus]

but a crash that could be blamed on negligence

I don't think anyone reasonable would consider crash in this situation. There were no crashes caused by volcanic ash, and those famous flights everyone is talking about flew straight into the dense plume (nothing even remotely like situation we have now) unaware of what was happening.

Chances of crash happening due to current situation over Europe are so remote that it's pointless considering them anymore than regular risk of flying.

What is worth considering for airlines is potential reduction in engines lifetime and premature overhauls. That is where accumulated losses vs. risks I was talking about come into story.

 

[mgb_phys]

What is worth considering for airlines is potential reduction in engines lifetime and premature overhauls. That is where accumulated losses vs. risks I was talking about come into story.

The BA flight 9 flew into a dense ash cloud and it's engines were essentially destroyed in minutes - so if you fly into an ash cloud 1% as dense are your engines unaffected, affect only 1% as much, have it's life reduced by 1% or be destroyed in a few *100 minutes?

After the flight do you have to do a regular engine walk around, a standard 1000hour boroscope inspection, a 4000 hour medium inspection of a 10,000hour full stripdown inspection.

Engines for a 747 are about $5-10M each - but just to complicate matters they are rarely bought, they are on a complex leasing/support contract with Rolls Royce, what does flying through an ash cloud do to your operations contract?

 

[Frame Dragger]

I don't think anyone reasonable would consider crash in this situation. There were no crashes caused by volcanic ash, and those famous flights everyone is talking about flew straight into the dense plume (nothing even remotely like situation we have now) unaware of what was happening.

Chances of crash happening due to current situation over Europe are so remote that it's pointless considering them anymore than regular risk of flying.

What is worth considering for airlines is potential reduction in engines lifetime and premature overhauls. That is where accumulated losses vs. risks I was talking about come into story.

You keep saying that the risk is remote, because in the past ash hasn't hindered air travel unles you're "flying into a dense plume". Yeah, for a couple of reason I could add:

1.) How long have major commercial pressurized flights been around?
2.) How many near-misses do you think anyone is willing to take with an expensive machine?
3.) Even if there is ZERO respect for human life, each person probably represents ~1 civil lawsuit or a MASSIVE class-action.
4.) You seem to believe that the cost of NOT doing business is in any way equivalent to the cost of a single crash.
5.) Ignoring a crash; pretend the ENGINES simply start to have issues. Better yet, forget that, just imagine that a small amount of volcanic glass DOES form, but it's only discovered upon landing. See mgb's 10,000 hour stripdown.
6.) You can't easily tell how dense an ash-cloud is from radar or from the cockpit by eye. You don't make assumptions with airplanes unless you're tired of living.

EDIT: The ACI and AEA (Airport associations, aka industry groups) are petitioning against the ban. Some flights have shown safe conditions. Here is one view... followed by another:

Olivier Jankovec, director general of ACI Europe, said airports have lost close to 136 million euros ($184 million U.S.) so far. More than 6.8 million passengers have been affected, he said in a statement, adding that the effect is worse than after the September 11, 2001, terrorist attacks on the United States.

More on how stranded travelers are coping

"While safety remains a non-negotiable priority, it is not incompatible with our legitimate request to reconsider the present restrictions," he said.

"While Europe's airlines and airports consider safety to be an absolute priority, they are questioning the proportionality of the flight restrictions currently imposed," ACI Europe and the AEA said in their joint statement. "The eruption of the Icelandic volcano is not an unprecedented event and the procedures applied in other parts of the world for volcanic eruptions do not appear to require the kind of restrictions that are presently being imposed in Europe."

But an expert who has flown over Europe to check the air said he saw "dangerous" conditions.

Guy Gratton, head of the Facility for Airborne Atmospheric Measurements at Britain's Cranfield University, flew into the skies Thursday and saw "a really strange and complex set of layers of ash," with a layer of perfectly clear air suddenly giving way to a layer of ash, he told CNN. If particles of ash enter a jet engine, when they come out they can solidify on turbine blades, he said.

A group of his colleagues took to the skies Sunday, and in some places saw "quite high concentrations of ash," he said.

"I suspect it's going to be a few days yet" before it's safe to fly, Gratton added.

Oh, and look, the head of someone who DOESN'T make money or suffer in elections doesn't think it's safe. And why?... because the layers are not homogeneous, are not easy to predict, etc.

http://www.cnn.com/2010/TRAVEL/04/18/volcano.ash.test.flights/index.html?hpt=T1

So, most think it's perfectly safe, except for those who don't. Given that, and given the amount of air traffic... do the math.

 

[ViewsofMars]

The BA flight 9 flew into a dense ash cloud and it's engines were essentially destroyed in minutes - so if you fly into an ash cloud 1% as dense are your engines unaffected, affect only 1% as much, have it's life reduced by 1% or be destroyed in a few *100 minutes?

Hi mgb_phys, I read on National Geographic News Watch from News Editor David Brawn's Eye on the World the following.

The giant cloud of ash called to mind the 1982 incident when a British Airways Boeing 747 flew through an ash cloud over Indonesia.

"A strange St Elmo's Fire-like light had appeared on the cockpit windscreen and sulphur-smelling smoke started filling the passenger cabin. Then, within minutes, all four engines had failed," the Telegraph reports on its website.

The plane managed to glide sufficiently out of the ash plume for three of the four badly damaged engines to restart. It had fallen 25,000 feet.
http://blogs.nationalgeographic.com/blogs/news/chiefeditor/technology/

 

[ViewsofMars]

Moving onto Monday, April 19, 2010 article by Martin Evans, Alastair Jamieson, Richard Alleyne and David Millward in the online newspaper Telegraph.co.uk., the article Volcanic ash cloud: British Airways fly in the face of ban.

The chaos caused by the eruption of an Icelandic volcano, now entering its fifth day, has left more than one million British travellers stranded abroad.

The unprecedented disruption to airline passengers, which has threatened to leave schools closed and businesses without workers after the Easter holidays, has already cost the economy £500million and is costing airlines worldwide £130million a day. Last night BA became the latest airline to challenge the necessity of the no-fly zone imposed by British air traffic authorities amid claims they had “overreacted”.

Willie Walsh, the airline’s chief executive, joined four crew in a three-hour test flight from London, over the Atlantic, to Cardiff. Today the airline will study the effects of the flight on engines before concluding whether it is safe to fly or not.

A BA spokesman said: “We would not be doing this if we did not think it was safe and didn’t have the necessary permission. We would not do anything which would jeopardise our crew or aircraft.”

The ban on flights is due to run until 7pm today at the earliest. The test flight came as Gordon Brown called a ministerial meeting amid suggestions the Government had been too slow to react. Five ministers – Lord Mandelson, Lord Adonis, Tessa Jowell, David Miliband and Lord West – lined up outside Number 10 after the talks to announce plans for Spain to be used as a transport ''hub’’ to try to get British travellers back home.

Spain’s airspace was opened up last night and plans were being made for British airline passengers to fly into Spain before being placed on naval or private ships to take them back to Britain.

With replacement bus, train and ferry services running out of capacity, the Tories earlier had proposed that ships be commandeered to get people back to Britain.

The Dutch airline KLM had earlier carried out a test flight through the ash cloud over Dutch airspace. A spokesman for the airline said: “We have not found anything unusual and no irregularities, which indicates the atmosphere is clean and safe to fly.”

Lufthansa also flew 10 aircraft from Munich to Frankfurt on Saturday with the blessing of the safety authorities.

A spokesman said: “We found no damage to the engines, fuselage or cockpit windows. This is why we are urging the aviation authorities to run more test flights rather than relying on computer models.”

Ulrich Schulte-Strathaus, the Secretary General of the Association of European Airlines, said: “Verification flights undertaken by several of our airlines have revealed no irregularities at all; this confirms our requirement that other options should be deployed to determine genuine risk”.

Last night Ryanair announced it was cancelling all scheduled flights to and from the UK, Ireland, Denmark, Finland, Norway, Sweden, Belgium, Holland, France, Germany, Poland and the Baltic States until 1pm British time on Wednesday.

Theresa Villiers, the shadow transport secretary, said: “With thousands of Britons stuck in airports overseas, it is hugely worrying that there is no end in sight for the flight ban. This crisis is costing the economy millions of pounds every day and causing huge amounts of travel misery.

''Those who are stranded abroad need reassurance from the Government that they are doing all they can to help get people home and address the crisis.”

The blanket ban was initially imposed on Thursday by Nats, the national air traffic control service.

Keith Bill, a spokesman for the pilots union BALPA, challenged Nats to prove that they have taken advice from counterparts around the world who have greater experience of ash clouds caused by volcano eruptions.

Jo Gillespie, an aviation safety expert, said: “Without having the data to back up the decision this looks like an overreaction and is hugely damaging to the already suffering airline industry.”
http://www.telegraph.co.uk/travel/t...d-British-Airways-fly-in-the-face-of-ban.html

 

[tomkeus]

I don't see how things Guy Grutton is saying are relevant for the entire continent. Ash plume is carried directly from Iceland towards the UK and the UK is most severely hit of all European countries.

What makes things tragic, everything points to entire Europe listening only to the British who are on the path of the direct impact and then just applying what they're doing to themselves. Ash info center is in the UK and their computational model just gives highest possible extent of ash plume disregarding it's density. I know for certain that Serbia and Montenegro, Croatian and Hungarian ATC closed down airspace based on UK Met's computer simulations and I'm fairly certain most of other air traffic authorities did that. No one did actual measurements. Only ones who did, were again, British who, being under highest impact, ofcourse measured high presence of ash here and there and just continue to scare the hack of the rest of the Europe without even considering that what they are measuring cannot be applied to the rest.

My point is: We have eruptions all the time There are procedures, and they certainly do not include locking down the entire continent. We had much stronger eruptions in the past but they didn't cause so much disruption in their respective areas. I mean, this volcano spewed out 150 million cubic meter of material. Met's map show that material distributed over at least couple of million cubic kilometers of atmosphere. Calculate mean concentration, and than take into account that concentration is higher in the areas closer to volcano and falls down further. I mean, the fact the people in the UK can see ash falling on the ground tells us that heavier things fall down from the sky in significant amount before reaching the continental Europe.

Basically, over greater part of closed down area ash concentration is negligible and airliners flying over Middle East or North Africa have to deal regularly with much higher presence of silicate particles in the air but no one is locking down anything down there.

Look at the Russians. They are flying without any lockdowns since this whole thing started. I didn't hear them complaining about the damage or planes falling from the sky.

 

[cristo]

I don't see how things Guy Grutton is saying are relevant for the entire continent. Ash plume is carried directly from Iceland towards the UK and the UK is most severely hit of all European countries.

Guy Gratton and his team flew into the cloud and took some data. Given that he is funded by the British government, it makes sense for him to primarily focus on the ash in British airspace. Just because no other data is being collected by equivalent EU entities does not mean he should be condemned for doing so.

What makes things tragic, everything points to entire Europe listening only to the British who are on the path of the direct impact and then just applying what they're doing to themselves. Ash info center is in the UK and their computational model just gives highest possible extent of ash plume disregarding it's density. I know for certain that Serbia and Montenegro, Croatian and Hungarian ATC closed down airspace based on UK Met's computer simulations and I'm fairly certain most of other air traffic authorities did that.

Really? Did you miss my post above. Here, I'll quote it for you:

Err.. firstly the simulations were not just done by the Met Office in the UK; simulations have been done by many other European equivalents. In fact, once professor whom I saw interviewed yesterday say that there was a remarkable level of agreement between the different simulations. Secondly, planes have been up there collecting data, and test flights continue to be done. However, it makes sense that such flights are done by suitable aircraft to try and gauge the situation, and not by just seeing whether a commercial airliner can fly through the ash.

No one did actual measurements. Only ones who did, were again, British who, being under highest impact, ofcourse measured high presence of ash here and there and just continue to scare the hack of the rest of the Europe without even considering that what they are measuring cannot be applied to the rest.

Are you an expert in these matters? Have you seen the data that the British researchers collected and passed on to the authorities, or the jet engine manufacturers? Did you hear the British researchers make sweeping claims applied to the entire continent?

My point is: We have eruptions all the time There are procedures, and they certainly do not include locking down the entire continent. We had much stronger eruptions in the past but they didn't cause so much disruption in their respective areas. I mean, this volcano spewed out 150 million cubic meter of material. Met's map show that material distributed over at least couple of million cubic kilometers of atmosphere. Calculate mean concentration, and than take into account that concentration is higher in the areas closer to volcano and falls down further.

Oh, I get it, the MET office are too dumb to think of this?

Look at the Russians. They are flying without any lockdowns since this whole thing started. I didn't hear them complaining about the damage or planes falling from the sky.

No, not yet, but then the Russians aren't really known for their air safety. Still, I haven't seen any maps, but it's likely that Russian airspace isn't affected to the same extent; their flights over Europe have likely been above the ash cloud.

 

[tomkeus]

My post was probably badly worded. I wasn't accusing UK Met of anything. I was accusing everyone of listening to them and making decisions without trying to understand what is behind the data.

Besides, it is not the Met who is deciding whether to close down airspace it is ATCs and bureaucrats. Met has qualified people who are not idiots unlike guys sitting somewhere in the office thinking to themselves are they going to be elected for the next term.

By saying that Russia isn't so affected you're just confirming my arguments. Met's maps show large portion of western Russia under the cloud, same as the rest of the Europe. Maybe the ash plume is just too afraid to go over the Russian border, despite what the simulations are telling it to do. BTW, Russians don't have significantly worse passenger air safety record than any other European country. It is just unfounded myth.

Here's another example: Ecuadorans have eruption of Tungurahua for years now but they're still flying. We could learn from them a thing or two.

P.S. Latest Met's map:

http://www.metoffice.gov.uk/aviation/vaac/data/VAG_1271655414.png

 

[Ivan Seeking]

Apparently the eruption has virtually stopped.

 

[mgb_phys]

My post was probably badly worded. I wasn't accusing UK Met of anything. I was accusing everyone of listening to them and making decisions without trying to understand what is behind the data.

The problem is that the Met office can model the movement of the cloud and to an extent the density of the cloud.
What nobody knows is how dense can you fly in?
You need a graph of ash-density vs damage to engine - at the moment there are two data points, no-ash=no-danger, lots of ash = lose all 4 engines in 10minutes.

In the absence of any data somebody will pick a number out of the air and in a few years this will become the standard for safe ash density, in the same way that someone decided that a 3.9oz bottle of shampoo is safe but a 4.1oz one is a threat to the aircraft.

 

[ViewsofMars]

Apparently the eruption has virtually stopped.

Best news I've heard today. Thanks Ivan. Where did you find that info?