In Defense Of The Met Office

Safety comes first. The people who were complaining should try flying in it. If they want to plummet 40,000+ feet to their deaths because the ash destroyed or severely damaged every single engine on board, I say they should go for it, and good luck to them. But they don’t have the right to gamble with other people’s lives.
I say the Met Office made the right call.

Steve, airplanes dont follow rails or tunnels, they can divert or change altitude. volcanic ash was never reported above FL350 and liners can fly at those altitudes. a diversion north of island (or where deemed suitable) would have avoided eventual ash without leaving thousands stranded and airlines with massive losses. airplanes on the ground eat money like crazy.
if you read the report about the famous BA 009 flight over indonesia, you will see that the flight was very eventful, with sant’elmo fires and very visible phenomenons reconducting to volcanic ash, but the pilots, unaware of the eruption, failed to recognize them. a total ban was truly and massively OTT.

Now that enough information has been gathered, the decision has been made to restore the flight schedules. It has been a very long week for travelers, but in terms of the required science and engineering – seven days isn’t very long when making life or death decisions

Seven days to determine what level of ash can safely be handled by jet engines. Billions of dollars lost.
Why were not the standards set years ago. Volcanoes are not a new invention. Iceland has been on the North Atlantic flight paths for a very long time. Why was nott his work done years ago?

An old aviation saying …….”It is better to be on the ground and wishing you were in the air, than to be in the air and wishing you were on the ground.” Imagine if there had been (or in the future… was) a serious ash incident.

Kind of funny for MJK to come in at this late date in defense of the flight ban when just about the entire world has agreed that it was an incredibly wasteful knee jerk overreaction, based on flawed computer modeling.
And Steve, I’ve got to agree with GianMarko – why a complete ban, when a simple diversionary flight path would have worked just fine? Add one stop for refueling if you must, and simply divert several hundred miles to the south.
Also, why not a flight overhead to see how high the ash levels were really going? What kind of useful “precaution” can be obtained from trusting computer models without any kind of real world verification???
There were many prudent, realistic choices available here – and none of them were followed. The path followed was that of the brainless apparatchik who is terrified of being assigned blame for anything, so he decides that zero activity at all is the only possible salvation.

I would feel fine about flying the route, as long as, the plane always had enough fuel to divert back to the usa airbase in greenland or NE canada.
In reality, i probably would not fly the route because i am afraid a cost-cutting, money-losing airline is not putting enough fuel on the plane.

The argument is not whether this was dangerous or not, but rather that the airlines and the passengers should make the risk assessment. The problem with the government making the assessment is that they are very risk-intolerant and will almost always make a decision that is too conservative.

Yes, they would simply have to circle until they crash and burn into the volcano because there are no divert airports between SEA and LHR. Canada has no airports at all, and there are no other countries between the West Coast and Europe.
Wait a minute, perhaps not…
http://community.seattletimes.nwsource.com/archive/?date=20020508&slug=websas08
It’s sad that most people have no clue about risk assessment. They’ll happily drive to the airport, but then worry themselves stupid about a bit of dust in the atmosphere, which has never caused a single airliner to crash.
http://news.bbc.co.uk/1/hi/magazine/8633484.stm

I think you are missing the point here. The Met off role in all this was merely to provide a forecast of upper wind direction and therefore the location of volcanic ash in the atmosphere at all heights to 36000 feet~approx. The zero tolerance was inflicted by the european and british governments. Therefore, if the met off model showed dust in the atmosphere all flights had to be stopped through that part of the atmosphere.
The difference here was that in past eruptions elsewhere in the world, planes continued to fly but at a distance from the eruption deemed to be safe. This was not a zero tolerance policy but a safety first policy. The zero tolerance policy is the same one being inflicted on us by the CO² loonies. The problem is identical. The authorities don’t know what amount of dust / CO² is safe so they impose their zero tolerance policy and everyone pays but them.
Aircraft engines inhale dust/sand/earth all day everyday, it’s fine, low density powder which does no harm at all. As the test flights showed, you need to be in the volcanic cloud, close to the volcano to suffer serious damage. If you applied their principle to everyday life you would stay in bed. There is a risk with everything we do and we consciously assess that risk as we go about a daily routine and we would never say “I’m not eating that beef because of CJD, or I’m staying on this side of the road because I might get knocked down

If flights had been allowed to proceed and one or two went down, who do you think would have been sued for it? The government agencies that allowed the planes to fly, of course. The fact that airlines lost money due to this natural event is the cost of doing business.

Madman: It is all part of the nanny state. People have the right to infinite contract. If we want to take to risk, and the airlines are willing to take the risk, then I do not see why there needs to be a ban. The only problem would arise if the airlines lied about the risks in order to induce customers. Besides, as I said, even if a few planes had crashed here and there, airplane travel would still be statistically the safest form of transport over the long term.

Whilst I don’t like to see professional people ridiculed for no good reason, & I know some of the people who work at the Met Office in Exeter, the perhaps over-reliance on computer modelling alone is not a good idea, even if it is Deep Thought! As I have said before, this thing can do 2 billion? calculations a second, but if what is being put into the blunt end & coming out at the sharp end is wrong, it doesn’t matter how fast your “puter” actually is, one just gets the wrong answer that much faster, but one doesn’t know it’s wrong. As others have pointed out elsewhere, a regime of air quality testing should have been in place almost immediately to assess particle dilution & density, & a little less “intolerance” from aero-engine manufacturers should also have been imposed, nothing has zero tolerances in my book! What happens to lower altitude planes in a dust storm?
Also, what about those aircraft already in flight? What are they supposed to do, put the handbrake on at 30,000 ft & stop for a coffee break for the duration? No, they would have to continue on their journeys & take a……risk. The problem is the EU itself among other things, the Met Office is simply a part of the problem, & as expected, Mr Everybody is blaming Mr Somebody, but Mr Nobody is taking responibility.

The plane disaster in Indonesia involved a plane at night that was unaware of the eruption. There’s no reason why flights couldn’t have been re-scheduled so that planes flew in daylight hours where pilots could see the airspace ahead of them. No planes were grounded when Pinatubo erupted which was a much bigger eruption.

Pat Moffitt (08:25:12) :
The Met was correct in immediately grounding the flights— their failure was not following up with testing
The Met Office don’t have the power to ground aircraft, they just provided the data for others (NATS and the CAA in the UK I think) to make the decision.
That said I’m happy and surprised to be in broad agreement with Steven Goddard.

Steven Goddard is completely off track.
No one wants an airplane going across an ash cloud.
As an ash cluod is released by a volcano, a math model can suggest where and how that cloud is moving.
Only observations, taken by military air crafts, satellite sensors, lidars, high land stations, can plot the real edge of the ash cloud.
The model is just a first guess of the ash movement.
If a first and fast reaction can be to close the air space downwind the eruption site, also with the help of a model, then you have to take measurements at once.
Instead, burocrats relied only on models. Real time observations were taken into account too many day later.
No other options ara allowed, at least reasonable ones!
P.S. Airplanes are faster then winds.

Your pushing of the “precautionary approach” might just pass the test of common sense in a theoretical world where the choice were between flying and not flying, but this is the real world.
People do not fly will travel by other means. There are people who have driven across Europe at the end of a long holiday with no real sleep for three days on the wrong side of the road and how many people in the Health and Safety brigade are taking responsibility for this clear and known danger to people’s safety?
Moreover, this whole shame has cost around a billion. The typical hospital costs 70million, so in order to fulfil someone idea of “health” we have effectively 14 less hospital’s worth to spend on health and transport infrastructure which would definitely cut deaths. Compare that to the “might have caused a plane to have a few problems which have been 100% recoverable from in the past even when they didn’t know there was a cloud”.
We in Britain are already facing severe cuts to services which do save lives. If as seems quite reasonable the airlines sue the Government for their incompetent handling of the scare there will be even less money for essential services. There won’t be the social workers to check on children at risk. There won’t be the money to repair the roads that lead to accidents on the roads. There won’t be the cancer care in the NHS. There won’t be the money in the economy to create the employment – and unemployment is a known contributor to mental health problems.
To put my views in short: if the Met Office and Government had spent more time worrying about real problems like volcano ash and did the appropriate science rather than listening to idiots like mann then there would have been the measurements to tell them that this was just a lot of hot air!

I’ve been on trans-Atlantic flights where another jumbo jet crossed paths within half a mile. No doubt a screw up, and the idea of quickly rerouting hundreds of jets around an unpredictable ash plume seems unmanageable.
The relative velocity of two jumbo jets in opposite directions is faster than the speed of a high velocity .22 LR bullet. How good are you at dodging several hundred bullets in the air at the same time?

Today’s consumer is unaware or unwilling to analyze risk. They just want ot get there. The airline should figure out how. Having seen what happened on the ground after Mt. St. Helens, with ash clogging air filters and ruining engines, I think the MET was totally correct at the start. Perhaps they held on too long, but a ruined engine in a car is an annoyance. A ruined engine (or two or four) in the air is a slightly bigger problem. You don’t always have Capt. Scully in the cockpit.

“”” MJK (08:16:04) :
Steven,
I could not agree more with this analsyis. It is the prudent, risk mitigating thing to do. What I cannot understand is why you do not apply the same logic to climate change. A large number of models and scientists are telling us to be prudent and take action yet you choose to ignore them and take a wait and see approach. I for one am extremely dissapointed that people such as yourself are taking such a huge gamble with our collective future. shame on you.
MJK. “””
Well MJK, perhaps the reasoning is that the very same people who are predicting; excuse me projecting, those not yet proven future maybes; using the exact same computer models that make those predictions; forgive me projections; also say that virtually nothing we do will have any perceptible effect on the outcome, which they say is already pre-ordained.
The “precautionary” principle, is often cited to support a belief in god, or allah, the creator; whatever euphemism you want to choose. If you believe and when you die, it turns out you were wrong; well no harm, you will never be aware you were wrong; but if you don’t believe, and you end up being wrong, then you are going to catch hell. So you might as well believe; it’s the safe choice.
It’s also the epitome of total selfishness; motivated by nothing but absolute self interest.
Note I am not making an argument against a belief in a supreme creator; simply citing an often given argument.
Does a useless waste of resources, that could better the lives of billions of present and future people; not also violate the precautionary principle.
Or to put it another way; if you send out five ships laden with cargo; following a belief that one of them, at least should be able to make it to the destination; what is your contingency plan to deal with the glut, in the event that all five ships arrive safely ?
With the route that Steven has plotted above, a very slight deviation beginning at Seattle could take the plane to the North of Iceland by enough to miss that prominent South East plume; with a minimal extra distance; but once you got past Iceland you have very little freedom of choice.
The MET office could be faulted for poor modelling; but they didn’t make the no fly rule. The overbearing European Union bosses did. Right now America is stampeding rapidly in their footsteps.
But MJK, I would suggest that your comparison of this somewhat minor geologic event; with a total destruction of the entire world economic base; because of a string of dire predictions (that’s PREDICTIONS); none of which have so far come to pass; nor find any parallel in the climate history of the planet over geologic time scales; is akin to driving a whole herd of bison over a cliff, just to get a steak for dinner.

Xi Chin (08:40:53) :
People can sign whatever they want, but their relatives are still going to sue the airline for everything they are worth.
I flew every few weeks to Europe after 9/11, and the planes were nearly deserted for almost a year. People were scared to fly. One plane going down in the ash would have been a much bigger loss to the airlines than one week of forced closure of the British airspace.
I was in Hawaii in June, 1974 when the movie Jaws hit the theaters. The swimming was great, because very few people were going in the water. People value their safety, and one incident real or imagined can have a huge impact on business.

Let’s review this post:
“Suppose you are taking a ten hour 8:30 PM flight from Seattle to London. You pass Iceland eight hours into the flight, and ash conditions may have changed dramatically since you left.”
1) Meteorological information is updated in flight.
2) Observations show the plume over the crater and in its close vicinity only was shooting up to 6,000m and that 50km away from it the plume was following the lines of cold air advection at an altitude comprised between 2 to 3,000m. Thus a small trajectory diversion could avoid the problem over Iceland.
“A new volcanic eruption may have occurred overnight, and your plane is almost out of fuel. No matter how accurate the circulation models are, they can not predict the behaviour of the volcano. The modelers and the people in charge of decision making have to be conservative.”
1) Is the volcanic eruption monitored of not? That’s what VAAC is all about.
2) Again the diversion is not in thousands of miles
3) You point out the circulation models and clearly there was a problem there: the concept used is critical to making provisional decisions. The ash plume was perfectly traceable, followed a known meteorological phenomenon (Leroux’s Mobile Polar Highs). Therefore the dispersal of the ash plume was predictable in this context both in space and in time, provided the Met had worked with the proper concept.
“Do you want to be on a plane over the frigid waters of the North Atlantic, which can’t progress forward and does not have enough fuel to turn back? I know I don’t. Erupting volcanoes can change in the blink of an eye, as people near Seattle found out at 8:32 AM on May 18, 1980. There is always going to be some risk, but this particular volcano has been spewing out a lot of ash and deserves particular caution.”
1) Of course not,
2) Hence the critical importance of working with the proper meteo concept and a quality monitoring of the ongoing explosive phase of the eruption, quite a difference with Mt. St. Helen.
3) Backing this concept with early measurement flights, and then make the decisions of selective closures.
“Now that enough information has been gathered, the decision has been made to restore the flight schedules. It has been a very long week for travelers, but in terms of the required science and engineering – seven days isn’t very long when making life or death decisions.”
1) Blanket precautionary principle is not science based decision
2) Suggesting that science and engineering of monitoring and measuring the ash plume predictable dispersal should take over 5 days to get going simply betrays the state of un-preparedness of the authorities.
3) Finally, the resounding silence of the climatically correct: those who, claiming to understand climate, are in fact predicting the occurrence of weather phenomenon in 2050 were nowhere to be seen or heard. It is true their prediction could have been verified in about a week. It was a real crisis to be managed and responses would attract scrutiny. 2050 is much safer…

I think Steve is right and wrong here.
1) It’s a good thing that the MET made decisions that they have. It’s extremely important to use the utmost caution when you’re talking about flights in the vicinity of volcanoes. Volcanic ash WILL shut jet engines down. There are numerous incidents of this. Check the NTSB incident reports. Prudence is the better part of valor. This is especially true in aviation.
2) He’s wrong, or just didn’t do any research on, the circumstances of a flight. There are very strict rules governing any flight, especially flights over water. There are specific fuel requirements, alternate landing sites, etc. No flight ever leaves the ground without fully thinking through potential emergencies at any phase of the flight.

Madman (08:33:32) :
The argument is not whether this was dangerous or not, but rather that the airlines and the passengers should make the risk assessment. The problem with the government making the assessment is that they are very risk-intolerant and will almost always make a decision that is too conservative.
Absolutely agree, and as others have said, this isn’t the Met offices fault. I would assume (hope!) they are doing the best with the data at hand.
The British Met Office has always come under fire for failure to predict.
Ignoring the risks one way or another, I think this does highlight the underlying fault of weather/climate prediction: it’s more often wrong than right [for a given individual or subset of individuals], yet people put immense faith in said predictions.
Ironically, this is a predictor of the AGW situation: those doing the predicting will not be the ones to bear the cost of actions [to be] taken to mitigate the risks. Likewise, they will not be the ones to set or enforce any rules to ensure the burden is taken up by those who are party to neither the predictions or enforcement.
To that end, when the predictors hit the limelight, even though they may not be the enforcers, it’s unsurprising those bearing the burden come after the predictors.

stevengoddard (09:03:19) :
I’ve been on trans-Atlantic flights where another jumbo jet crossed paths within half a mile. No doubt a screw up, and the idea of quickly rerouting hundreds of jets around an unpredictable ash plume seems unmanageable.
It only seems unmanageable to you, because you have no clue about what is involved. You seem to be like Khan. You are intelligent, but not experienced. Your pattern indicates two-dimensional thinking.
http://en.wikipedia.org/wiki/Separation_%28air_traffic_control%29#Vertical_separation

The world runs off computer models these days.
Weather models from NCAR and The Met Office are very accurate. You can even run NCAR’s weather models on your Windows PC.
http://www.mmm.ucar.edu/wrf/users/downloads.html

Steven Goddard
I suspect if all airport security was stopped,there would be a lot of planes crashing or exploding.Interesting article in the WSJ about Alaska airlines.
http://online.wsj.com/article/SB10001424052748704133804575198183757930998.html?mod=WSJ_hp_us_mostpop_read
There are 3 incidents of airplanes flying through ash,but all engines did recover,so perhaps the risk is over stated.
In 1982, a British Airways 747 near Jakarta, Indonesia, flew through an ash cloud at 37,000 feet from the Mount Galunggung volcano. All four of its engines choked on ash and flamed out. The 747 glided for 13 terrifying minutes. Ash filled the cabin through air vents and the cockpit window was severely scratched.
End
I say Let people choose,if they are warned of the risk,and decide to accept that risk,the airlines should not be able to be sued if a plane did go down.
I wonder if the people travelling on Alaskan airlines have any idea that there is a risk,when their planes are travelling after an eruption?

Dear Steven
I think you are being too magnaminous to the Met Office and Nats. The line you have drawn could easily be adjusted soutward to miss Ireland and come in from the west without any change in distance. The analogy is with a segment of an orange.
My reading is that the quantity of material was not measured and there were two different maps showing where the cloud was positioned.

Many keep saying/thinking the Met Office closed the airspace. It did no such thing – it provided advice on the presence/absence of ash. Eurocontrol and the transport ministries made the closure decisions based on that *advice*.
Those agencies should have been aware of the limitations of what the Met Office can provide given the limited tools and observations MO has. Will these agencies, or the airlines, now fund a program to provide enough observations to verify/disprove the ash dispersion models for the next event?
Right now using a jet-engine teardown to verify ash concentration is like using tree rings to determine annual temperature. We need more and better thermometers, not proxies.

Rob Honeycutt (10:02:35) :
Volcanic ash WILL shut jet engines down. There are numerous incidents of this. Check the NTSB incident reports. Prudence is the better part of valor. This is especially true in aviation.
I don’t mean to be snarky here but I think a correction is in order: Volcanic ash in high enough concentration will shut engines down.
Everything seems to indicate that the concentrations of ash need to be substantial to shut an engine down and even then the reported failures do not appear to have been catastrophic.
I’m not saying we should blindly ignore risk, or that the initial shutdown was incorrect, but the invocation of a “zero tolerance” policy based on computer projections and not real-world verification was a ridiculous overreaction.
The proper management of this issue, past an initial grounding period, should have been to find the plume, altitudes, and concentrations… and to selectively restore routes when it could be verified that they were not at risk.
Prudence is necessary, no disagreement, but the term prudence implies that a certain level of reason is involved in the equation.

Where’s the polar ice cap ?

Phil. (10:49:23) :
Hu McCulloch is right – you’re not.
http://www.nasa.gov/externalflash/Glopac/
http://www.nasa.gov/centers/dryden/research/GloPac/glopac_instruments.html
The Global Hawk can fly at altitudes up to 65,000 feet. Its range is greater than 10,000 nautical miles and its endurance is greater than 31 hours.
And it’s equipped for the job!

Boo!
Did you you jump at all scare- easy-crowd?
Why would the flight path be assumed to be a straight line to begin with? And is flying close to Iceland, when a volcano is actively spewing out ash, a requirement?
The transatlantic airliners could’ve gone by route of New York, Washington DC, Miami, to Ireland, Portugal, Spain, Italy, France.
From Seattle one could open up a corridor by way over Siberia to Europe as well.
Did they shut down the whole west indies, and all countries around, a few weeks back?
Met Office ought to be sued back down to earth.

The problem is that too little is known about aircraft risks due to ash. The only thing that we know is that if we fly through areas with high ash concentrations we risk extensive damage. We don’t know exactly how high these concentrations are and not what the damages will be at different concentrations. That is why airliners take puts security first and disband all flights, although the margins might be wide.
To reroute air traffic to lower altitudes where the concentrations are significantly lower is impossible in practice.
There would be completely new schedules, which means that ALL flight schedules at ALL airports would have to be recalculated. Those who have read mathematical optimization at universities know how difficult it is to create such optimal planning. Today it is mostly based on experience gained from many years of air traffic.
It is much more difficult to fly on lower altitudes since the air space consist of zones around airports where exact guidance is needed from control towers. Air routes on higher altitudes are more or less straight lines and divided in lots and lots of altitude segments, and navigation is aided by GPS.
It would concentrate too many aircraft within the same area and therefore also increase the risk of collisions.
The aircraft would consume more fuel due to a denser atmosphere and due to more complicated flights (shorter distances and fewer passengers). The current tables for calculating fuel requirements/passengers/luggage would no longer be trustworthy and they would need to take extra wide margins when taking onboard fuel, which would lessen profits. Regarding the bad economy of most airliners this would be out of the question.
To conclude, even with the super computers of today, even a temporary air traffic change would be almost impossible to do.

Liar (10:38:34) :
What is different about this volcano is that it is located upwind of the world’s busiest airport, in a region where the weather and visibility is normally poor.

Symon (10:33:47) :
Interesting statistics, thanks. I’m far more concerned about the drive to DIA than the flight itself. I rarely get there without seeing at least one serious accident on I-25, which is one of the most dangerous stretches of overcrowded, narrow highway I have ever seen.

The modelers and the people in charge of decision making have to be conservative.

Do you mean overly-conservative or appropriately conservative?
Do you think they should balance their conservation with risk management analysis frameworks?

Retired Engineer (09:18:38) :
Today’s consumer is unaware or unwilling to analyze risk. …

This is exactly what I have been fighting just recently! I’m also an engineer and this is jailor who attaches the chains which anchor us to a nanny state.
The perception of a ‘safe’ world is more pervasive today than it has ever been. The outbreak of cellphone laws (which we won’t go into here) is a symptom of this. All risk has been assumed by some others: the ability to ‘insure’ practically anything has disavowed the individual of all risk, although the risk still exists.
Since the perception is one of a ‘risk free’ world, when something goes wrong it is patently obvious it *must* be someone elses fault…

Steven:
The Met office didn’t ground the flights and the “blame” (if any) needs to be on the decision makers. My criticism has been the reliance upon models instead of actual data.
I also agree it’s best to err on the side of caution.
People are amazingly unable to calculate risk in their everyday lives. How often do you see people talking on the phone or texting while driving in heavy rush-hour traffic?

I don’t know if anyone will read this far… but here are the issues:
The Met Office job was to issue a SIGMET (Significant Meteorological) warning of the presence of Volcanic Ash in a defined volume of airspace moving in a defined direction. No-one has yet pointed out that if the model was inaccurate when it showed where ash should be, then it must also be inaccurate showing where airspace was ash-free; this is a far more dangerous and worrying consideration!
Normally it is the responsibility of the aircraft operator to avoid the SIGMET defined volumes that they believe would hazard their aircraft. What we saw from the EU and various countries was a assumption of the aircraft operator role by governments who put on the ground-stop and did not allow operations.
Volcanic ash rarely causes aircraft engines to fail: the aircraft has to be flown into very dense ash for a failure. However, volcanic ash does damage turbojet engines and makes them increasingly inefficient. Flying in the presence of low concentrations of volcanic ash can therefore cause the engine maintenance period to be greatly shortened and the level of maintenance to be greatly increased.: This is a significant cost to the operator. The decision to fly or not in the dispersed volcanic ash cloud is therefore a commercial/b> decision NOT a safety risk management decision.
It is the lack of clear identification of responsibility and imposition of authority – and the assumption of the role of decision maker by often inexpert governments that is upsetting the aviation industry.
Just a few other points – the minimum separation standards currently in oceanic airspace are 30 nautical miles laterally and in trail and 1000 feet vertically. That is for aircraft with navigation systems that meet the Required Navigational Performance of 4 nautical miles containment. For those with RNP of 10 nautical miles the separation is 50 nautical miles laterally and in trail.) In airspace with radar or other surveillance cover it is 5 nautical miles and 1000 feet.

767s have a range of 9,400 to 12,200 km. The distance from LAX to LHR is almost 9,000 km.
Not a lot of room for error.

Essentially all modern weather forecasting is done using computer models. Thousands of lives are saved every year because of the ability to forecast hurricane movement a few days in advance.
About 100 years ago, an unexpected storm hit the Great Plains and hundreds of school children got lost and died walking home from school. That doesn’t happen any more.

>The distance from LAX to LHR is almost 9,000 km.<
What happened to the Seattle example? And what about flights originating in New York?
And all flights could have diverted to Reykjavik if needed. That was upwind and open, right?

stevengoddard (09:32:20) :
I was flying the Atlantic every few weeks after 9/11 and I was not aware of the reduction in passengers that you talk about . I get the impression you are making it all up or your imagination is too vivid.

stevengoddard (10:15:18) :
Rob Honeycutt (10:02:35) :
It is one thing to have one distressed plane, and quite a different management problem to have dozens or hundreds of them at the same time.
Unless they were all flying in formation, that would be an unlikely scenario. The ash cloud would have to be of a uniform density over the entire area and at each altitude the aircraft were transiting, and the first aircraft encountering the ash cloud would probably request an immediate deviation, probably to a higher altitude — and there’s enough separation built into the standards to accommodate that. Deviation requests for avoiding unforecast severe turbulence are more common than you’d think.
So, you probably wouldn’t get more than a half-dozen in actual distress, but you probably wouldn’t one to be on one of them…

Jeremy (13:19:17) :
The no fly zones were extended to areas where it was believed there might be a safety threat from the ash.

UK John (13:10:16) : “All other days the sky was remarkably clear, clearer than normal for UK, wherever I went in UK.”
Jet planes are profoundly affecting the global weather because their jetstreams “seed” high-altitude clouds. Ground the planes and you have these “remarkably clear” days, days which used to be taken for granted. Probably the single most significant man-made effect on the climate, I think.

Steven,
no offence meant, but you dont seem to understand how commercial air tranport works, i suggest talking to an airline pilot to get some proper info.

I spent several years doing research on explosive volcanic eruptions, and developed a healthy respect for them.
http://www.driever.nl/foto/achtergronden/JLM-NatGeo-Mount-St-Helens-1980-May-18.jpg

wobble (13:13:02) :
I didn’t realize that the wind always blows the same direction in Iceland.
Mike Borgelt (14:41:13) :
So what you are saying is that the EU decision to shut down the air space was stupid and was my fault, EU fusion research is stupid and corrupt, and nuclear proliferation from breeder reactors is of no concern. It is difficult to debate against such well articulated logic.

In 1989, a KLM Boeing 747 that flew through a volcanic ash cloud above Alaska temporarily lost all four motors. The motors restarted at a lower altitude and the plane eventually landed safely.

I also think that the “risk” should have been the airlines to take, they could easily have informed passengers that they were going to drastically reduce flights (which would have at least given people a chance to get home and change plans). Flying directly through newly released ash is a no-brainer… but more diffuse clouds just shorten the already-required maintenance cycles of very expensive aircraft.
To see air traffic control in action during an “event”, watch

and the similar “linked” videos on the right side. These FedEx videos have always amazed me, as others mentioned they “look like ants”.
In fact, I’m amazed at the variety of opinions on this topic. I tend toward the “there’s no such thing as zero risk” camp, and firmly believe it should have been left to the people with the equipment and reputations at risk, NOT governments. I’m a bit disappointed at those saying there was a dramatic danger that was unacceptable to fly in, because that is just not the case.
However, thanks to this being discussed here and elsewhere, a lot of people are learning that the Met office models are not all they’re cracked up to be, so the end result is acceptable to me.

Kay (08:14:27) :
Safety comes first. The people who were complaining should try flying in it.
No, it looks like money comes first.
A family friend of ours from Germany was supposed to visit us for 4 weeks, and was supposed to arrive last Sunday in LAX.
Obviously that flight was cancelled.
No contact with the airline (Lufthansa) by phone either, even after she waited for 2 hrs in the voice-mail hell.
This Tuesday (2 days ago), she went to the airport ticket counter after it was announced that flying would resume.
The people at the ticket counter told her:
1. The “hotline” phone line is not monitored by people. They simply did not man it during the no-fly time. As people could not fly, there was no point in spending manpower helping the stranded passengers.
2. Because she bought a ticket that was lower in price than a regular full fare ticket, the earliest she could fly was May 2. She bought the ticket directly from Lufthansa, which had special fares before this volcano thing.
She also would have to return at her original return date, cutting 2 weeks of her planned vacation, because after that date no flights would be available (booked out they said).
3. She could fly right away, if she upgraded to full price 1st or business class.
4. Lufthansa would gladly take back her ticket and refund what she paid for it.
After she did 4., she went online and bought a new ticket at a quite a bit higher price. Plenty of seats available (same airline), and no problem with her return flight date either.

stevengoddard (11:27:42) :
Steven, have you driven 17 from Santa Cruz to Los Gatos? If you have, knowing how much weed those CA stoners have smoked, and you think flying through an ash cloud is dangerous, I’ll retire hurt!

Mike McMillan (16:37:31) :
Can you see through a cloud of volcanic ash, at night?

Steve,
are you a sceptic or a contrarian??

kuhnkat (17:10:33) :
I am a scientist/engineer. I am interested in the truth.
The title of this article is “In Defense Of The Met Office.” I understand that some would like to blame all the evils of the world on Met Office models, but I haven’t seen anyone present any evidence that the Met Office did anything wrong.
Heathrow receives over 400 long haul flights per day. That means there are a lot of flights over the ocean in the air headed to London at any given time. And Heathrow is just one airport of many in Europe.
No doubt some small airstrip in Greenland can handle hundreds of diverted jumbo jets though.

Come one this is silly
Yesterday New Scientist was saying global warming is causing the ash fall.
What happened today? http://translate.google.com/translate?js=y&prev=_t&hl=en&ie=UTF-8&layout=1&eotf=1&u=http%3A%2F%2Fwww.ruv.is%2F&sl=is&tl=en did global warming fail?

The Guardian has a detailed summary of the process behind the decision to reopen the air space:
http://www.guardian.co.uk/uk/2010/apr/21/airlines-battle-skies

Amid mounting evidence from airline test flights that it was safe to fly through the ash, EU transport ministers agreed on Monday evening that “safe flight zones” could be established in the ash if national air safety watchdogs sanctioned it.
At the same time, the aerospace giant Airbus ordered test flights of its own from Toulouse. An A380 took off into the French no-fly zone on a route that lasted three hours and 50 minutes. A second test aircraft, an A340-400, flew for five hours, crossing over into German airspace.
Both planes were checked on landing and the inspection reports sent to the CAA and manufacturers that evening.After poring over the historical data and results from test flights, manufacturers one by one said their engines could safely fly in volcanic plumes with up to 2,000 micrograms of ash per cubic metre.
“They agreed that it’s acceptable for that level of ash to be tolerated without any real restriction,” said McKenna. A new safety code was roughed out: anything more than 2,000 micrograms per cubic metre is a no-fly zone. Between 2,000 and 200 micrograms requires planes to take extra precautions. Below 200 micrograms is considered no threat at all.
But by Tuesday morning, those doubts had yet to crystallise into a sweeping rule change. Walsh was arguing that the BA test flight proved that flying through low-density ash clouds was safe – a finding backed by dozens of tests around Europe. The CAA still had to run its findings by a board meeting on Tuesday, however, with the airline executives reconvening at Marsham Street at 7pm.
With the clock ticking as BA84 approached UK airspace, the CAA told Walsh and his peers that the board approved new guidelines that would allow flights through the ash – overturning years-old regulations in 96 hours.
The BA boss had one question, according to the government source. “Willie then said: ‘What does it mean for my flights?'” CAA officials conferred with colleagues in Ireland and came back with the answer: you can land at 10pm. In fact, BA84 landed at 21.49pm, minutes after Adonis announced the changes on the steps of Marsham Street, becoming the first flight to grace Heathrow in nearly six days.

Another SEA-LHR aviation route map, identical to the one in this article.
http://avise1.com/route-map/

stevengoddard (17:00:13) :
Lots of experts posting here who know more about my experiences than I do.

Well, now that you mention it, we can takeup the challenge and give it a good go around (smile).

Here is the flight path from SEA-LHR
http://gc.kls2.com/cgi-bin/gc?PATH=SEA-LHR&RANGE=&PATH-COLOR=&PATH-UNITS=mi&PATH-MINIMUM=&SPEED-GROUND=&SPEED-UNITS=kts&RANGE-STYLE=best&RANGE-COLOR=&MAP-STYLE=
Just like in the article.

A flight path is not a Great Circle, and a Great Circle is not a flight path. The Great Circle route is in the simplistic sense the shortest segment of a path between to points along a circle around the globe. Commercial jet flights follow jet routes as mapped on jet route navigation charts in conformance with ICAO guidelines, international agreements, and national authorities. Flight planning attempts to prepare a flight plan which takes the flight between waypoints along the jet routes which are advantageous with respect to weather, the effect of upper level winds upon fuel burn and flight times, air traffic on the jet routes, segemnts of multiple Great Circles, fuel temperatures, and an assortment of other considerations. Consequently, each flight on a given service route varies from previous flights. They virtually never actually fly on the Great Circle route, which is why the Web page you linked to says, “Great Circle Mapper. This information may not be accurate or current and is not valid for navigation or flight planning. No warranty of fitness for any purpose is made or implied.” Accordingly, your link is not actually fit for the purpose of illustrating the navigation of your actual flight path.
The GPS TV station you say gave your position fooled you. It is, in fact, the flight information channel of an IFE (In-Flight Entertainment) system. It too is not fit for the purpose of flight planning or flight navigation. They come in a number of varying capabilities and configurations, so the exact functions cannot be exactly described without knowing exactly which system was in use. However, the flight information channel of the IFE systems typically display what they describe as the “simulated” position of the aircraft. The simpler implementations of the flight information channel use the Great Circle route for the service route as proxy graphic for the total flight. The GPS unit used to orient the antenna for the IFE video entertainment also provides the information necessary to position the aircraft graphic along the proxy Great Circle route, service route, or map graphic. Despite the usage of GPS to orient the IFE antenna, the actual position of the aircraft is often kilometers, tens of kilometers, or hundeds of kilometers on either side of the “simulated” flight path and position presented on the SBE display as a relative indication of the progress of the flight along the idealized service route. It gives the passengers some “entertainment” to keep their minds busy.

And I was most definitely on a flight which nearly collided with another plane near Greenland. I was looking right out the window. But I do understand that air traffic controllers and pilots never, ever make mistakes, and all are experts on the effects of volcanic ash on jet engines.

There is a lot of skepticism about claims of near mid-air collisions on long-haul flights; because few passeners understand their sighting of another aircraft flying by at very close distances with closing speeds of around 1,200 miles per hour is done routinely in complete safety, deliberately, with no danger of collision, and no reason to be alarmed. It is not unusual to see a child’s face in the other aircraft’s passenger window where the Sun shines in as the other aircraft flashes by close enough to see faces. This surprises many people. What was it about the encounter which made you think it had to be an unauthorized near miss and near mid-air collision versus routine air traffic with legal separation of the aircraft?

RACookPE1978 (19:59:40) :
Your methodology might work for demonstrating that there is not a problem, but suppose it finds unacceptable levels of ash? It would provide no information about areal extent.

Steven, I was almost with you until the
” stevengoddard (19:11:20) : The Guardian has a detailed summary of the process behind the decision to reopen the air space:”
Never never never use the Guardian word! Now go and wash your mouth out with soap and water 😉
Anyway, the planes are now back up in the air (and seem to be staying aloft), people are getting home or off on holiday/business, so let get back to the real job in hand!

D. Patterson (20:34:19) :
One of my favorite things about the GPS systems on the planes, is that on the westbound flight I can watch the topography of Greenland out the window, and correlate it with the map on the TV. The correlation is excellent. There have even been a few times when the westbound flight went right over Iceland, which was a real treat.
The GPS systems on display are very accurate representations of the location of the plane. You can see rivers and towns as you cross them in real time.

http://www.csmonitor.com/USA/2010/0418/Should-planes-fly-in-Iceland-volcano-ash-Be-careful-study-says.

Should planes fly in Iceland volcano ash? Be careful, study says.
Some European airlines have begun test flights to see if it is safe to fly through the volcano ash from Iceland’s Eyjafjallajökull. But a NASA study says a little ash can cause serious problems.

stevengoddard (17:49:48) :
kuhnkat (17:10:33) :
I am a scientist/engineer. I am interested in the truth.
The title of this article is “In Defense Of The Met Office.” I understand that some would like to blame all the evils of the world on Met Office models, but I haven’t seen anyone present any evidence that the Met Office did anything wrong.

Matthias Ruete, the European Commission’s director general of transport has done so. The Met Office caused the closure of European airspace by using a computer model, NAMES III, to forecast the size, location and density of the volcanic plumes. Unfortunately, the Met Office failed to conduct more than four actual observations to provide real world data to confirm the accuracy or lack of accuracy of their computer model forecasts. The Met Office then compunded the alleged errors by continuing the computer model forecasts despite contradictory empirical evidence from satellite observations. Is it not wrong to use inaccurate fantasy models relied upon decisionmakers when empirical evidence conflicts with those unreal models?

Heathrow receives over 400 long haul flights per day. That means there are a lot of flights over the ocean in the air headed to London at any given time. And Heathrow is just one airport of many in Europe.
No doubt some small airstrip in Greenland can handle hundreds of diverted jumbo jets though.

Only a small number of commercial trans-Atlantic flights are beyond return to North American or European airports at any one time.
Keflavik IAP (IATA: KEF) has two runways with heavy jet capacities greater than 10,000ft. lengths. It has the capacity of landing all trans-Atlantic flights operating in its area. There are several other airfields also capable of landing trans-Atlantic flights in the event of an emergncy.
Greenland has a number of airports and airfields capable of taking non-emergency and emergency landings of trans-Atlantic flights.
There is no reason to fear a problem with availability of airfields on the trans-Atlantic routes or an excess in trans-Atlantic flights requiring emergency landings.

stevengoddard (22:20:12) :
D. Patterson (20:46:09) :
I have taken the SFO to LHR flight dozens of times and watched the GPS map repeatedly. The eastbound flight follows that route until it passes Iceland, then turns a little south in order to approach London from the west, passing over Ireland.
A really poor debating technique is to start a sentence out with “You don’t understand.” I understand just fine, thanks.

It isn’t a debating tactic. It is a simple statement of obvious fact. Otherwise, you would not conflate an illustration of a Great Circle route or Great Circle service route with an actual flight path. Just because the aircraft is in close proximity with its approach to a waypoint in the vicinity of Iceland does not mean the aircraft is always following the great circle segemnt of its flight plan elsewhere along the actual flight route. It’s like a clock with a rundown battery. It displays the correct time twice a day, despite the stationary hour and minute hands. Your “simulated” flight information channel is going to be exactly correct upon departure from Seattle, upon arrival at London, when flying over or by a waypoint, and along the Great Circle route whenever the jet route and flight conditions permit a close correspondence between the route and actual flight path. Nonetheless, they are not the same thing, and they are often, not always, far separated between intermediate points. Of course, you would know that if you filed a flight plan, read a JNC, and navigated an aircraft. You would also understand how a flight level of 4 to 7 nautical miles makes it difficult for the non-aviator to recognize how many nautical miles the aircraft may be off cources while still flying within 10 or more nautical miles of the baseline course.

D. Patterson (23:10:56) :
Suppose a large eruption occurs at night. Tracking the ash plume is not possible with radar. The only way to locate the extent is by visuals (dependent on clear skies) or by computer models.
Hundreds of planes fly east over the North Atlantic at night, and they would have no clue where it is safe to fly. Here is the forecast for tomorrow
http://www.turbulenceforecast.com/atlantic_eastbound_tracks.php

stevengoddard your understanding of jet Airliner operations is greatly in error. D. Patterson’s understanding is Waaaay closer to reality than yours. I’ve been flying for over 50 years and spent 9 months based in Los Angeles flying the B742(airline jargon) on the KLAX – EGKK route, and did about 40 sectors. AirNZ at the time had about 40 different routes for that sector. The flight planning computer would calculate the minimum cost route and that is the route that we would fly on the day(night mostly). The tracks varied from about 500 nautical miles north of the great circle track to 1000 miles south of it, at midpoint. In flight re-routing at ATC request was quite common. I don’t recall ever seeing another aircraft anywhere between Churchill and nearing UK but was pre TCAS.
Quite a good article, with minor errors.
http://online.wsj.com/article/SB10001424052748703816204574487173981612780.html
Anyone who wants to worry should worry about birds. Many people killed and aircraft destroyed. Sully was VERY lucky. I believe 50th percentile(or maybe a lot lower) pilots would have done as well; there were no other choices.
http://www.int-birdstrike.org/Warsaw_Papers/IBSC26%20WPSA1.pdf
http://www.detect-inc.com/birdstrikes.htm
By the way the FAA thinks you( in the vernacular, not personal, meaning) shouldn’t know about bird strikes.
http://www.pprune.org/rumours-news/367608-faa-proposes-keep-bird-strike-data-secret.html
AirNZ was very lucky to not lose a B742 on take-off from Christchurch in1986 I think. Two engines failed due multiple seagull ingestion. Fortunately one hydraulic air-pump(an allowable deficiency) was unserviceable so they had done a flap 10 T/O. If they had been in normal flap 20 configuration they WOULD have crashed. As it was it was very close.
I have personally had three bird-strike incidents. Worst was a dozen or more Godwits at about 400 feet on T/O runway 23, in a B737, at NZAA. One or more ingested by starboard engine( we could smell the cooking). Engine did not fail. Carried out a visual circuit at 500 ft(nice excuse for a bit of fun) for a safe landing.

stevengoddard (23:36:20) :
D. Patterson (23:10:56) :
Suppose a large eruption occurs at night. Tracking the ash plume is not possible with radar. The only way to locate the extent is by visuals (dependent on clear skies) or by computer models.
Hundreds of planes fly east over the North Atlantic at night, and they would have no clue where it is safe to fly. Here is the forecast for tomorrow
http://www.turbulenceforecast.com/atlantic_eastbound_tracks.php

If the Met Office is blind, it’s by their own misguided choice and over reliance upon computer modeling at the expense of budgets for confirmable observational methods. There are numerous alternatives. To make a long story short, see the following for just one example:
Volcanic Ash Principal Component Imagery – Basic Information
http://rammb.cira.colostate.edu/research/goes-r/proving_ground/cira_product_list/volcanic_ash_pci.asp
As an aside with respect to aviation:
http://www.nwas.org/committees/aviation/volcanic_ash/Vol_Ash_Enroute_Avoidance.html

>>stevengoddard (15:37:05) :
I didn’t realize that the wind always blows the same direction in Iceland.<<
Regardless of what happens tomorrow or in the future, Keflavik International Airport has yet to close throughout this ash plume concern. It would have certainly been a viable divert field for European bound flights.
Steven, it's laughable that you attempt to assert adequate aviation expertise derived from passenger seat GPS displays and window viewing. Many of us with professional aviation experience don't think you've made a convincing case regarding the actual risk.
Fight us if you wish, but there's a reason we are disagreeing with you.

>>paul jackson (23:31:20) :
Just yesterday I looked up into the sky and saw clouds at different altitudes moving at right angles to each other. Because of this the models are heavily safe-sided.<>If it’s such a financial hardship for the airlines to be grounded for safe-sided ash predictions<<
You're missing the point by focussing on financial hardship for the airlines. Grounding the airlines caused financial hardship to hundreds if not thousands of businesses which were disrupted.
The risks should have been accurately assessed for the business decision makers. It's wrong to artificially inflate the risks just because little is actually known about the risks.

I do agree that they did the right thing in the face of not knowing. What I think they and others do deserve criticism for is the total lack of supporting measurements. That should have been in place a long time ago. I know that it might still not have mattered as noone has real data on the effect of different concentrations and distributions of dust/grain size and type but I believe that engeneering judgements would be possible. In the current case, without real measurements everyone was left in the dark and the best option was to stop flying.

Gregg E.:
“You volunteering to be on one of those 1 in 1000 planes that’d crash?”
No, but I was willing to take my chances that the plane I chose would not be one of those. In the long run, flying is the safest way to travel. Don’t you know this? You have a higher probablility of getting hit by a meteor than dying in a plane crash!
Besides, even when some as ash did affect a plane, you gotta look at the facts. The fact is, it was all okay in the end. Just like a bit of extreme turbulence. Drop below FL350 using the old 15 degree glide slope trick, spark up the engines again, then land at the safest conginency airport and fill out risk assessment forms. Eezzie Piezzie.

Accuracy of the models, one issue. Airline safety, other issue. I think it is great to see the models laughed at in 50 point type. On the other hand, I have flown transatlantic and transpacific flights more times than I can remember, and most of the time is spent over some pretty lonely airspace with available airports for emergency landings few and I don’t think the word “far” in “far between” really covers it, few and vast distances, even for a jet, between.
A one in ten thousand risk is unacceptable for a flight, there would be smoking craters everywhere if it wasn’t. They made the right call, models or no models. Using models was just an extra bit of fluff they didn’t really need, and that only could have given them false confidence.

In the circumstances described the proper thing to do would be to allow planes to keep fying but redirect them further to the south., possibly requiring them to refuel in the Azores or Spain. That would certainly cause a lot of inconvenience but far less than what we have seen.
In any case I believe that the cloud has been at up to 30,000 ft whereas intercontinental planes can fly at 50,000 ft. The main problem is when they come in to land.

As I understand it the NAME model was developed to predict the areas which would be safe in the event of a nuclear explosion, rather than predicting where it would be dangerous. Due to deterministic chaos, it is impossible to know exactly where and how dense the dust cloud will be within the potentially contaminated area, from minute to minute.
In view of the fact that the manufacturers of jet engines had a ‘zero tolerance’ policy to ash until the last couple of days, I agree with Steven that on this occasion the Met Office are not to blame.

Richard Briscoe (00:12:12) :
The “point” is that The Met Office has taken heat, when they did nothing wrong.
acementhead (23:49:26) :
Of course the track varies some depending on winds. How is that in any way relevant to the discussion?
Grumbler (00:30:55) :
Neither the military nor NASA are convinced that the ash levels are safe. An ash cloud can not be picked up by radar, and that is exactly why they had to rely on computer models.

FrankS (06:52:18) :
The point is that Europe was suddenly dealing with a new and unpredictable situation. Every eruption and every hour of an eruption is different than previous ones.

I have been reading these comments and one recurring theme is “there should be zero tolerance for volcanic ash” or words to that effect.: and If there is any chance whatsoever of volcanic ash then the aircraft must not fly.
So when we get another Pinatubo or Krakatoa or a similar huge eruption that spreads ash all around the globe lasting in some cases for years – should all flying worldwide cease for those years?
There is a level of volcanic ash that can cause a turbojet to fail no-one should or would want to, fly into an ash cloud of that density. However, as the ash density reduces it becomes a case of engines needing further maintenance and more detailed after flight inspection and this moves the decision making from a SAFETY decision to a COMMERCIAL decision.
There is almost always volcanic ash in the air – just like sand from dust storms which is just as damaging. Sand from the Sahara regularly settles in northern Europe. Calls for ‘zero tolerance’ for ash sound ‘responsible’ but are just demonstrating an ignorance of reality. There are densities of ash beyond which it is commercially punitive to fly and beyond that as density increases it becomes unsafe. The aircraft operators and their flight crews are the correct decision makers on whether to fly and what are the commercially acceptable and safe routes.

stevengoddard (06:21:57) :
You have instead attached your argument to an incorrect claim that airplane GPS maps aren’t accurate.

Are you serious? You’re using a strawman to label my argument a strawman???
I never claimed that airplane GPS maps aren’t accurate. I’m claiming that your aviation experience is obviously weak if it’s limited to passenger GPS maps and gazing out the passenger window. And it’s kinda funny that you would use those examples to prop up your credibility with this respect.
Have you ever chosen an alternative airfield? Have you ever determined a fuel load? Have you ever diverted? Have you ever been forced to choose between being overly cautious and getting the mission accomplished?
My only point has been that the Met Office should have been honest about being clueless and simply allowed the experienced decision makers within the aviation field to do their jobs.
Think about it like an intelligence officer not being honest with his commander. It’s not the intelligence officer’s job to substitute his cluelessness with inaccurate assessments in order to be cautious. If there is a lack of good information, then it’s the commander’s (the decision maker’s) job to be cautious. The intelligence officer simply needs to convey accurate information, and that includes accurately conveying what he doesn’t know.

It shouldn’t have applies for short hall hops across Europe. Your only in the air for an hour or less. Yes the dust was dangerous over Scandinavia but the further south you went the clearer it appears to have been. Ash doesn’t show up on radar but it does show on ladar and some millimetre radars. The air-forces should have had both. Mapping a safe route on an hourly basis with out relying on climate modeling computers, that have a bad track record, should have been done. Transatlantic flights should have been possible via north Africa and the Azores.
The Governments and Airlines also botched the process of quickly getting more trains and buses on the tracks and roads.
The no fly strategy was cooked up for places like Indonesia and the Philippines. Places where you could survive without a flight or two. Europe needed a real plan, it still needs one. No one has noticed yet but people will have died on organ waiting lists.
Hopefully Ladars are being installed in pods that can be mounted on airforce jets to get a better map of the dust. A few in the air could map safe corridors like an Icebreaker opening the way for shipping. With low wind speeds the corridors would not have changed fast.
Raphial Morgado is going to have a big win eventually since his MYT can be configured to run with dust filters on the intakes while still getting several times the power to weight of a jet engine. http://www.angellabsllc.com/index.html

wobble (08:27:11) :
Please tell us about your aviation experience flying jumbo jest through ash clouds.

Please tell us about your aviation experience flying jumbo jest through ash clouds.

First. I don’t have any experience flying jumbo jets through ash clouds.
Please tell us about your aviation experience flying jumbo jets through ash clouds.
Ash clouds notwithstanding, I have substantial aviation experience flying in that part of the world. Such experience allows me to see the folly in your point about the Seattle-London flight, and it allows me to ask you about a New York-London flight.
I only called you out for asserting authoritative experience based on passenger window/gps gazing despite what you’re being told by many of us with practical experience.
Second. What does this have to do with my point? My point is that the decision makers should have been told the truth, and the truth was that the Met Office didn’t have a clue about the risks.
Third. Your claims that the Met Office did nothing wrong is inaccurate and baseless.

wobble (10:48:17) :
You are making all kinds of accusations in various directions without providing any evidence to back them up.
If you are claiming that SEA->LHR flights don’t normally pass over Southern Greenland and then south of Iceland, you are incorrect.
http://www.travelmath.com/flight-distance/from/SEA/to/LHR

stevengoddard (12:03:31) :
You are making all kinds of accusations in various directions without providing any evidence to back them up.
If you are claiming that SEA->LHR flights don’t normally pass over Southern Greenland and then south of Iceland, you are incorrect.

steven,
You really need to slow down.
I’ve never made any claim about a typical flight path. I only ever took issue with your claims about aircraft range, and then I asked you to try apply your same logic to NEW YORK – LONDON flights (which you’ve conveniently ignored). But none of this has ever been my main point.
Stop defending the actions of the Met Office. It doesn’t matter how right you think the grounding decision was. They were wrong to have misrepresented their confidence in their models. They should have admitted their cluelessness and allowed the decision makers to do their job in the absence of information. The outcome may have been the same, but that’s not the point.

wobble (12:18:47) :
The decision makers have to plan based on the longest flights. A 767 travelling from the western US to London does not have a lot of extra fuel. BA’s DEN->LHR flight uses a 767, and I have taken that flight a dozen or so times.
Show some evidence that The Met Office misrepresented their models.

George Tetley (12:35:28) :
Everything you said is true. Now please tell us about your experiences flying through volcanic ash clouds.
A 767 has a maximum range of 10,400 km, and my flight from Denver is over 7,000 km. How does that “get the pilot home?”

stevengoddard (12:30:29) :
Show some evidence that The Met Office misrepresented their models.

They issued depictions of ash plumes which they represented as accurate.

stevengoddard (12:20:53) :
You said that you are a scientist seeking the truth. Unfortunately. You have a number of people who have tried to help you do so. Unfortunately, you appear to be interpreting these remarks, intended as helpful or not, as some kind of personal attacks. The sarcasm is not necessary. I asked a question. It was not styled as sarcasm. It was not meant as sarcasm. It was a straightforward and plain question which did NOT make a rhetorical assumption that you did not read or understand the link. It was an effort to discover why you appeared to disregard the information found there.

That imagery is not available for Europe and only works if there is no cloud cover.

I already acknowledged that the GOES East satellite lacked the critical capabilities of the GOES West satellite when I first mentioned it. That is precisely why I suggested some critics may find the Met Office culpable for neglecting to invest in appropriate observational systems while spending exorbitant sums of money on unreliable computer modeling systems. The necessary satellite and satellite imagery could have been in place when needed. The excuse that Iceland’s volcanic eruptions were unexpected also do not withstand scrutiny. The London center was established for the specific purpose of maintaining a watch over the volcanic ash risk from Icelandic volcanoes.
You keep assuming and saying the volcanic dust is not detectable at night. This is simply not ncessarily the case. Satellites, when suitably equipped, can image some of the denser volcanic ash clouds using infrared imagery. Commercial flights can in many cases observe volcanic ash clouds at night if they are also visible in daylight. The link I provided gave you the procedures for detection and avoidance while inflight. These were provided as just a few samples from a larger number of potential methods already in use for many years and many decades. Thirty five years ago I was using infra red imagery from much more primitive satellites to disseminate NOTAM and SIGMET alerts.

One million people a week pass through LHR. Are you going to bet their lives on your theories?

One of those people was my wife’s nephew. He was stranded in London when the European flights were grounded. While neither he or his family have any desire to see him put at unnecessary levels of risk, they seem to understand that the massive scope of the groundings were unnecessary and inappropriate. He has expressed his unhappiness with the situation in no uncertain terms. He is not a tourist. He is traveling on business, and there are consequences when the flights are grounded unnecessarily. He mentioned how the stranded passengers have a far greater risk of being killed as pdestrians in a European crosswalk, in an automobile accident, and in a European train wreck than a crash of an airliner failing to avoid the volcanic ash clouds. Of course, that was his opinion about his own life and risks, which you obviously do not share.
Personally, I’ve flown aboard a commercial flight through the invisible dust of the Mount St. Helens eruption. I’ve flown aboard military flights conducting observations and research during a variety of volcanic eruptions, sandstorms, and great forest fires. The risks while real, proved to be quite manageable. Financial loss for aircraft safety and maintenance has been the far greater risk. Like many situations in life, the risks can be managed and minimized. If you are not satisfied, you can choose to not fly without using state authority to deny other people the right to govern their own lives and make informed decisions about the actual risks they face. Never forget, there are also risks to be faced when saying on the ground and traveling by other means.

stevengoddard (12:20:53) :
One million people a week pass through LHR. Are you going to bet their lives on your theories?

Their lives are at risk every single week with or without a volcano ash plume.
And I still want to know the number of people that died because flights were restricted.
Decreased air travel = Increased highway travel = Increased deaths

Another article from one week ago :
http://news.sky.com/skynews/Home/UK-News/Iceland-Volcano-Eruption-Why-Is-Volcanic-Dust-So-Dangerous-For-Aircrafts/Article/201004315602761?lpos=UK_News_Carousel_Region_1&lid=ARTICLE_15602761_Iceland:_Volcano_Eruption_Why_Is_Volcanic_Dust_So_Dangerous_For_Aircrafts

Former British Airways pilot Eric Moody has first-hand experience of flying through an ash cloud.
In June 1982 he was piloting a Jumbo 747 from Kuala Lumpur to Perth, Australia when he hit an ash cloud just off Java.
“It was very frightening, all the engines stopped for 14 to 15 minutes and we didn’t know what was happening,” he told Sky News.
“It was dark and the effect was of St Elmos fire around the aircraft. We were looking for the cloud that had caused it but didn’t know it was a volcanic ash cloud.
Former BA pilot Eric Moody flew through an ash cloud
“We glided the aircraft about 80 nautical miles and went down 37,000ft to about 12,000ft.
“That was when we must have come out of the bottom of the ash cloud. It was a dark cold night.”
As a result of Mr Moody’s flight experience research into the effects of volcanic ash clouds on aircraft increased and Volcanic Ash Advisory Centres were established around the world.
“Flying into volcanic ash is as deadly as flying with ice on your aircraft,” said Mr Moody.
“And everyone knows how dangerous that is.”
This disruption in the UK is being caused after a massive cloud of ash from a volcano in Iceland drifted into UK airspace.
Several UK airports are closed and hundreds of flights have been cancelled.

In defense of Steven Goddard, not that he needs it.
wobble (12:53:16)
(excerpt)
The decision makers can, instead of restricting all flights, simply require all London bound flights to plan to land with a minimum amount of fuel depending on the type of aircraft (or published max range flight time equivalent given the type of aircraft).
=======================
Hauling around extra fuel cuts into the already minimal profit margin, and doesn’t do any good if the engines aren’t running due to ash injestion.

CodeTech (15:06:23) :
I agree completely. The Guardian posted a good chronology of how that process worked over the past week.
http://www.guardian.co.uk/uk/2010/apr/21/airlines-battle-skies

1DandyTroll (15:49:36) :
It is up to the prosecution to prove guilt, not the other way around.

u.k.(us) (14:36:27) :
Hauling around extra fuel cuts into the already minimal profit margin, and doesn’t do any good if the engines aren’t running due to ash injestion.

You’ve successfully missed the point.
The extra fuel would be used to avoid flying through ash. The cost of the extra fuel is a business decision. It’s certainly not a decision for the Met Office.

CodeTech (15:06:23) :
One death on the road is an “accident”. One plane going down is hundreds of deaths and is a tragedy, and is unacceptable.

What about an extra 1,000 deaths caused by the increased highway traffic? Are those 1,000 deaths acceptable?
Do you agree that:
Decreased air travel = Increased highway travel = Increased deaths

Perhaps uniquely on this thread, I am a pilot who regularly flies across both the Atlantic and Pacific.
There are three main problems with volcanic ash:
— melting in the combustion section and subsequent blocking of cooling passages in the engine
— windscreen abrasion
— invisibility to on-board radar
The last of these is the critical factor, because, in principal, volcanic ash clouds are no more, or less, hazardous than thunderstorms.
Therefore, the EU could have opened airspace under the same rules similar to those that apply to aircraft with inoperative WX radar: day and clear weather. (simplified to avoid a blizzard of pilot talk)
There would have to be an additional restriction which is no different than operating over mountainous terrain: driftdown performance (i.e., the altitude the airplane can fly after the failure of one engine). Just because the ash cloud tops out at, say, 25,000 feet doesn’t mean you can legally fly over it, unless (more pilot talk with caveats about how we can fly over the Himalayas).
As for maneuvering to avoid an unplanned ash cloud encounter en route, in principle this is no different than maneuvering to avoid convective activity. There are well established, and frequently used, procedures to deal with this sort of thing.
So, from the cockpit, I thought the EU’s blanket airspace closure was idiotic, a perfect example of nanny-state risk avoidance run completely amok..

wobble (16:29:09) :
u.k.(us) (14:36:27) :
Hauling around extra fuel cuts into the already minimal profit margin, and doesn’t do any good if the engines aren’t running due to ash injestion.
You’ve successfully missed the point.
The extra fuel would be used to avoid flying through ash. The cost of the extra fuel is a business decision. It’s certainly not a decision for the Met Office.
========================
Avoid the ash, land at an alternate airport, and drive back to the original destination?
Circle the destination airport until fuel reserves force a diversion?
Allow all air traffic into a possibly contaminated airspace, and hope for the best?
Wait till an aircraft flames-out, then close the airspace?
IMHO, a tough call.

wobble (12:18:47)
…..They should have admitted their cluelessness and allowed the decision makers to do their job in the absence of information. ………….
============
decisions were made, apparently by decision makers.
Seems you don’t agree with the decisions made by the makers.