In Defense Of The Met Office

By Steven Goddard

As reported on WUWT, The UK Met Office is taking a lot of heat for airline financial loses, caused by no flight rules during the Icelandic volcanic eruption. Many readers have expressed their agreement with those criticisms.

I don’t agree with all of these criticisms, and here is why.

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.  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.

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.

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.

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313 thoughts on “In Defense Of The Met Office

  1. 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.

  2. Are you arguing that the Met Office were correct in pushing their inaccurate ash distribution model – as they were effectively factoring in the risk of new eruptions? What else can the program do – predict meteor showers (?) (we know it isn’t particularly useful for weather prediction).
    I am beginning to suspect that the Met Office simulation fortran program features a large array called ‘W’, a large number of mysterious integer offsets into this array, that only Julia claims to be able to understand, and after chewing through large amounts of compute time, it either prints out ‘No’, ‘Maybe’, or ‘Much hotter’.

  3. 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.

  4. 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.

  5. 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?

  6. Steven,
    A couple of qualifiers to this discussion:
    1.) Commercial flights are rarely “nearly out of fuel” – even then, your point is an appropriate consideration for international flights but not local European flights.
    2.) If there was, as you say, a new eruption it would take some time for the ash to get into the flight path for Heathrow – there could always be a new eruption and this is something that has to be managed regardless. The concern is what’s going on in the flight path of a given flight.
    3.) A big part of the complaint is that the MET almost, if not completely, exclusively used computer models to predict dispersion. They also appear to have gone off of a zero tolerance policy. Without confirmation by real measurement, there was no way to tell if the risk was even real or just the figment of a computer’s imagination.
    This is a disagree without being disagreeable moment as far as I’m concerned – hope there are no hard feelings. If anything, this seems to be a nice lesson in the risk of reliance on computer models paired with alarmism.

  7. 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.

  8. The Met was correct in immediately grounding the flights— their failure was not following up with testing. Additionally, risks are not always avoided- they are often transferred. Automobile travel per passenger mile is significantly greater to passengers and pedestrians than is air. Zero air travel risk causes increased auto risk– the question is where is the inflection point?

  9. 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.

  10. “gianmarko (08:14:55) :
    Steve, airplanes dont follow rails or tunnels, they can divert or change altitude.

    I agree with this. Would adding 800 miles to this journey be so bad?

  11. 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.

  12. i. If there was an unexpected eruption then one need only drop below FL350, and divert to GLW or EDH. Sin problemo.
    ii. The statistical fact is that even if we sustained 1 airplane loss in every 1000 for a week or so, airplanes are so safe that in the long run they would still be the safest form of transport. So I don’t see what the problem was.

  13. 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.

  14. Steven,
    You suggest that many object to the notification of an eruption or a general warning of ash cloud. I disagree, I think the criticism is directed at the longer term use of the models to project ash cloud locations when they have been shown to be inaccurate. Clearly, observation is the more accurate method of locating the ash clouds. Also, the criticism seems directed at the aviation authorities moreso than the Met Office. If the Met deserve criticism , it is that they appear not to have properly advised authorities on the limitations of their model. The great failure here is the failure to implement an observation scheme to locate ash cloud extent and to identify just how much ash constitutes a dangerous level. I do take your point that some may direct their criticism inappropriately.

  15. 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

  16. That explains the first ± 2 days of flights on the great circle route, as shown on the graphic. Most reasonable people would agree with that. Looking at some of the many other images recording the volcanic action leaves one to wounder about subsequent days and closing the whole lot for such a long period.

  17. 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

  18. This is exactly why we see the faults in The Met Office models.
    The met uses models and can’t gather actual data from observation. Yes the plane flies at an altitude higher than the “plume”. The plane also flies faster than the dispersion of the plume. If a plane flies west to california, it’s actual ground speed is still greater than the jet stream it flies into. If the cloud travels at 80 miles an hour and the plane flies at over 400, it can out run the ash cloud safely.
    So if a plane takes off from Seattle, we calculate it’s speed and we can get wind direction and speed at varius altitudes applied to the volcanoe, we may still beat it to Heathrow when the eruption is at the same time.

  19. 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.

  20. Steve, while I understand the decision to be cautious, I also have sympathy for the position of Lufthansa airlines which said.
    “The flight ban, which is completely based on computer calculations, is causing economic damage in the billions. This is why, for the future, we demand that dependable measurements must be available before a flight ban is imposed.”
    This statement was made after Lufthansa sent ten Boeing 747 and Airbus 340 jets on transfer flights from Munich to Frankfurt. They flew to a height of 24,000 feet. After the flights the planes were examined by Lufthansa technicians in Frankfort where they didn’t find the slightest scratch on the cockpit windscreens, on the outer skin nor in the engines.”
    Once again, the Met Offices use of computer models failed miserable proving they are no substitute for actual real world measurements.

  21. 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.

  22. I freely admit I dont understand people who say things like “Safety comes first” (let alone those who screech it it).
    If safety comes first then these people wouldn’t leave their houses, since driving is one hell of a lot more risky than flying. Indeed, you’d need about 50 volcanos constantly erupting to make flying as risky as driving.
    Just because the airline schedules the flight and the flight crew agrees to fly the plane doesn’t mean the passengers are forced to get on it.
    “safety” is an infantile fantasy, and people who think it is more important than anything else give me the screaming hee-bee jee-bees. Especially those who claim to be highly focussed on their personal safety and then blithely hand their lives over into the jdugements of bureaucrats … take some responsibility for your own decisions, please!

  23. Yes, the immediate risk of death is worth some caution. Especially because if you’re near to Iceland and have to change course to elsewhere in Europe, you need a lot of extra fuel to make 45-to-90 degree turns and fly hundreds of extra miles to go around a wide cloud. If you’re really worried, fly to Italy via Rio de Janeiro.
    The above only concerns the risk of death to passengers of one flight. For the airlines and passengers, money is a strong secondary factor. If the volcano’s cloud is always below 35,000 feet, any plane which can stay above 45,000 feet can reach Europe once – it might destroy its engines during descent, and that is an expensive repair. Airlines have to first protect their passengers and secondly protect their planes or they can’t afford to fly. People who can afford to pay for new airplanes are always an exception. Passengers of diverted flights might find themselves in the wrong country and have to spend time and money traveling to their destination (at least within the EU there should be few legal travel complications – imagine if your flight was diverted to a place which required a visa which you didn’t have).
    Flying out of Europe is a different situation, as the engines may be damaged at the start of the flight. However, the return flight has to be considered by passengers planning to travel to Europe. Why fly there if you only have time and money for a two-week vacation, and you might not be able to leave there for several days? Do you plan to try to leave 4 days early? If you’re on a tour you may have little flexibility in scheduling.
    MJK – I do not fear a one or two degree change in temperature, and after looking at the science I think it is not likely that our CO2 has caused much change. Our black top roads and humid lawns have indeed caused local changes.

  24. please notice that at any rate even the worst case of flying into a volcanic ash cloud, the famous BA009 flight, didnt result in fatalities. engines were heavily damaged and flamed out but could be restarted at lower altitude.
    http://en.wikipedia.org/wiki/British_Airways_Flight_9
    lots of info on this flight and even a veryt good documentary in the well known series on discovery channel
    as for the comment about cost cutting airlines not loading enough fuel, that is nonsense. aircrafts cost substantially more than fuel, and no sane person would intentionally fly an airplane without enough fuel to reach destination. moreover, there are strict regulations about the necessary endurance for passenger flights.

  25. 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.

  26. As I understand it, the MET was only providing predictions about the behaviour of the dust clouds, which turned out to be roughly correct. They were NOT involved in the decision making about closing or opening airspace. You can’t blame them for someone else being overcautious.

  27. 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.

  28. The Met Office did the only thing they could do given their lack of completely accurate ash information. They know the models are liberal estimates of potential impact and that conditions can change in a very short period of time rendering the models useless and putting lives at risk.
    The fact is (according to what I’ve read so far/use a grain of salt), the satellites in stationary orbit aren’t capable of tracking smaller and dispersed ash particles. Other technology like ground based lasers and weather aircraft weren’t available.
    The issues do beg a question. They knew that the volcanos were “due” to go off and are likely to continue for quite some time. Why weren’t they better prepared to mitigate the situation and will it be any different down the road?

  29. 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.

  30. 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.

  31. If drone spy/attack planes work in Afghanistan, it should be possible to build a drone jet to fly through the cloud and see if there are any problems. Just 1 or 2 of these could stand by to cover any spot in the world.

  32. MJK (08:16:04) :
    Suppose for the sake of argument that there is significant risk from CAGW one hundred years in the future. The prudent course of action is to develop new low carbon energy technologies like fusion – now.
    Once those are in place, the problem takes care of itself. I have been a big fan of fusion for the last 35 years or so.
    http://wattsupwiththat.com/2009/05/24/energy-availability-is-almost-infinite/
    The airplane problem is different, because the time window is so much smaller.
    I have a huge amount of confidence in the idea that technologists freed from politically motivated budgets can accomplish amazing things, like the National Labs used to do before ERDA was mandated by Congress.

  33. 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!

  34. Met Office didn’t ground anything – just provided predictions of where the ashy stuff was likely to be found. NATS closed the airspace. If MO are supposed to know about whatever particle type and density affects jets engines I shall be staying on the ground in future.
    I still maintain their weather forecasts are not forecasts, but commentaries, as they change many times a day. Can’t plan to leave the house without some input from a piece of seaweed.
    And they said we would have 10 days of “hot” weather and it’s still cold unless you stand against a south-facing wall.

  35. 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?

  36. Of course you’re right! But there’s always a but in a discussion of this type. A number have been posted; more will no doubt follow. When humans leave the thinking to a stupid computer and stop searching for a different and safer, or as safe, solution to their problems, it’s time to make like a lemming and head for the cliff. You’re right! The Met (and the EU clones) gave it their best shot! The airlines obeyed! BUT, nobody used their brain to get over, under, around, or through the filpping problem –and that was wrong.

  37. 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.

  38. Heathrow normally handles over a million passengers per week. If they lose say 1,000 of them – would anyone notice? That is only 0.1%.
    The odds of getting killed by a terrorist blowing up your airplane are very small, so perhaps we should get rid of all airport security too?

  39. “”” 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.

  40. Mike Haseler (08:58:58) :
    Don’t worry, Mike. There are loads of non-essential public sector jobs that could be cut without affecting front-line services, I posted some of them earlier this week. They are all the politically correct stuff ‘n nonsense jobs that don’t do anything useful, other than to pry & inerfere with peoples lives. Tap into the Taxpayers Alliance website & search for the Unison ad! It’s quite amazing what could be cut to save billions of £s.
    Trouble is if the Conservatives get in they’ll do it, if Noo Labour get back in, they’d make the front-line cuts to schools, hospitals, care facilities just to be “bloody” minded.
    AtB :-))

  41. 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.

  42. This is a great issue. It illustrates the difference between government control versus a free people acting without government control:
    1. Governments cannot process multi-dimensional issues well. So they descend to making binary decisions on the basis of single parameters: Ash vs No Ash, Fly versus no Fly. Free people in free markets process many dimensions of cost, benefit, and risk and hungrily consume and digest information, and then create many differing decisions, the results of which add further information to the mix.
    Then you get nuanced decisions like: Fly where there is little or no ash. Do not fly where there is a lot of ash. Test for the presence of ash with test flights of planes, if needed, and assess the effect of varying levels of ash on engine performance. Maybe you cancel flights from Seattle, but not flights from NYC and Miami, etc.
    Whether on climate issues, volcanoes and flying, regulation of international finance, or a host of other issues, the cancer-like growth of governments in the last century bodes ill for our freedoms, prosperity, and enjoyment of life.
    KW

  43. Steven,
    A flioght from California to London will take a semi transpolar route (that is, it start heading north not in the straight line on your image), becasue as the EArth rotates to the east the flight will approach London from the north (a much shorter distance than flying over a paralel) and will never fly over Island.
    Flights from Argentina to Australia in the past used a transpolar route and arrived to Melbourne and Sydney from the south, not from the east crossing the entire Pacific Ocean. Transpolar flight make a kind of parabolic course, not reaching the 90ºS or 90ºN latitude… but barely making it to 70ºS or 70ºN. 🙂

  44. 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…

  45. “For an international flight the FAR regulations require each of the following criteria:
    1. Fuel to fly to destination. In other words a Dispatcher will either use manual charts or computer software to determine how much fuel a flight will need to takeoff or land at the prescribed airports. These fuel figures known as fuel burns take into effect the aircraft weight, type of engine, and weather which my effect the flight segment.
    2. Fuel to fly to the most distant alternate. The FAR regulations require that each flight have an assigned alternate airport if the weather cannot be forecasted within a three hour period of the flights arrival if the weather is not good enough so that the pilot can see the field over three miles away and the clouds are not lower than two thousand feet. If multiply alternates are listed the Aircraft dispatcher than fuel to fly to the most distant of the airports must be accounted for in the required fuel. On flights that are over six hours long an airline must assign an alternate airport and account for the fuel required.
    3. Fuel to fly for an additional ten percent of the total time Enroute. In other words, however much fuel is required to get from takeoff to destination an additional ten percent of this figure is added to the required fuel.
    4. Fuel to fly for an additional thirty minutes at normal cruise speed. The FAR requires that after a flight flies to its destination and to the alternate if necessary the aircraft needs to have an enough fuel to fly for an additional thirty minutes.”
    SOURCE: http://ezinearticles.com/?Air-Travelers-Survival-Guide—Will-My-Airplane-Run-Out-of-Fuel?&id=1373099

  46. 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.

  47. Eduardo Ferreyra (09:54:00) :
    I used to fly from SFO to London on a regular basis. The eastbound flights go over southern Greenland and pass just south of Iceland. Sometimes the westbound flights travel right over Iceland.

  48. 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.

  49. Government employees are usually conservative in their decisions, due to fear of losing their jobs. They go wherever the “tide” goes, NEVER against the wind.

  50. 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

  51. StevenGoddard:
    “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.”
    That might be true – but it is the Airlines’ decision whether or not to take that risk, not the Met office.

  52. 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.

  53. 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?

  54. 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.

  55. Henry chance (08:39:37) :
    This is exactly why we see the faults in The Met Office models.
    The met uses models and can’t gather actual data from observation. Yes the plane flies at an altitude higher than the “plume”. The plane also flies faster than the dispersion of the plume. If a plane flies west to california, it’s actual ground speed is still greater than the jet stream it flies into. If the cloud travels at 80 miles an hour and the plane flies at over 400, it can out run the ash cloud safely.
    So if a plane takes off from Seattle, we calculate it’s speed and we can get wind direction and speed at varius altitudes applied to the volcanoe, we may still beat it to Heathrow when the eruption is at the same time.

    And where do you think those winds aloft forecasts come from? The same computer that’s used to predict the dispersion of the plume (which contrary to your erroneous assertion it does very well). The Met can and does collect data from observation and uses it to update the forecasts as do the other 8 VAACs in the world. After Mt St Helens, Redoubt, Jakarta etc. in the 80s IATA put together the system of VAACs to cover the world instigated programs to develop models to provide reliable forecasts. A program which has been very successful in providing accurate predictions and has been credited with reducing the number of volcano related incidents.
    Steve and I frequently disagree but on this subject we are in agreement. It is really annoying to see guys like Alan the Brit make completely nonsense remarks on here. “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. The point that is missed that the right answer comes out of the ‘sharp end’ as indicated by testing carried out in multiple events. The Met (actually the London VAAC) did what it was supposed to do it gave a very good advisory to the aviation authorities who made the decision based on established protocols. This is the same procedure that all the VAACs follow all over the world. They should be thanked for their work not pilloried because of political and financial concerns.
    Also there’s a lot of nonsense about other aviation matters, ‘the plane can outfly the plume’ for example, not if the plane is flying in the opposite direction! On entering an ash plume your procedure is to execute a descending 180º turn at idle, you do not climb out of it, and set up best glide, ~240 knots at a glide ratio of ~15 so you’re dropping at about 1600 feet/minute. Above about FL 200 you’re outside the relight envelope so if any engines flame-out you can’t restart them for some time. In the case of the BA747 they were less than a minute away from doing a 180º and ditching in the ocean at night. In the case of the Redoubt 747 they were a minute away from impact too.
    Regarding fuel resources, planes do carry a required reserve sufficient to divert to an alternate with a time reserve, suppose you’re en route to London and UK airspace is shut down so you divert to Paris or Frankfurt along with a load of others and get stacked up waiting for a runway, everybody running low on fuel. As I recall when US airspace was shut down on 911 39 planes diverted to Gander a largely unused airport, imagine that happening in Europe in already busy airspace. (those are the two busiest airports in Europe, LHR ~500,000 traffic movement/yr))

  56. 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.

  57. Steven Goddard:
    “The odds of getting killed by a terrorist blowing up your airplane are very small, so perhaps we should get rid of all airport security too?”
    I agree, it would be a good idea to get rid of airport security. Even better, let us exercise our 2nd ammendment and we can protect ourselves!
    Besides, if there is such a massive terror threat – why arn’t the terrorists just blowing up department stores? There is no security there and more people. Perhaps the terror threat is an illusion used as an excuse to increase restrictions on travel. Think about it. Put yourself in the shoes of a terrorist. You want to blow something up. Why? Er, because that’s just what you do! Run with it! The airports have all this security now. Why would you not attack department stores instead? Why risk getting caught at the airport with all that security? Surely they would have switched to department stores by now? And don’t mention the tube and bus bombings because that was not “AL-CIA-DA” related. Why are Al-CIA-DA only focused on airports, where most of the security is run by Israeli companies (aka Mossad fronts)?
    Some people say it is because airplanes are “higher value” targets. WTF? Are they joking? If Al-CIA-DA blew up a few department stores then the major western shopping centres would grind to a halt. In a consumer society, that is about as high impact as it gets. Imagine body scanners in every store, the restriction on movement would make people only go out for essential items.
    There may be a reason why this is not happening though. Perhaps there actually are no bogey men! There are so many issues with the official story of 911 (see e.g. Architects & Engineers for 9/11 Truth) that it is difficult to beleive in the bogey men anymore.
    I don’t beleive in bogey men. I would rather have no security at airports, the same as we don’t have it in department stores, because I think that if these bogey men wanted to blow me up they would just as soon do it in a department store as in an airplane. Besides, even if there was a real terror threat to airplanes (but stragely not to department stores!), what are the odds of it being my plane? They are too low for the amount of hassle we have to go through every time we get on a plane, that’s for sure.

  58. 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.

  59. stevengoddard (09:32:20) :
    “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.”
    You might be interested that a team of researchers from Cornell University estimated there were at least 1,200 more deaths on America’s roads than there would have been, as a result of people being afraid to fly after 9/11. Shutting down a very safe form of travel as result of a tiny perceived risk, as NATS and the CAA did this last week, can only increase the carnage on the roads.

  60. stevengoddard (10:05:38):
    Eduardo Ferreyra (09:54:00) :
    I used to fly from SFO to London on a regular basis. The eastbound flights go over southern Greenland and pass just south of Iceland. Sometimes the westbound flights travel right over Iceland.
    * * * * * * * * * * * * * * * * * *
    Steven, were your flight non stop, or had a stop over in the East Coast? Because transpolar flight are quite common.

  61. stevengoddard (09:03:19) :
    You reveal that you do not know much about commercial airline operations despite your apparent heavy use of them. Your example of a aircraft crossing in opposite directions is not a ‘screw-up’ – the aircraft are separated by 1000ft in altitude or 5 nautical miles if at the same altitude. I can assure you that 1000ft vertical separation looks precious little from the cockpit but all the aircraft are certified to maintain their authorised altitude very accurately (Required Minimum Navigation Performance – RMNP).
    You also chose a bad example for your post. After take-off from Seattle a 747 would be unlikely to be able to reach an altitude in the stratosphere (ie above 36,000ft). For fuel efficiency reasons, however, it will step climb to higher altitudes as the flight progresses and may reach 39,000ft before approaching Iceland. Since Ejyafjallajokull has not been shooting ash clouds into the stratosphere (11km altitude – about 36,000ft) there is no mechanism by which significant ash could get that high so it would be OK to fly your plotted route.
    http://www.evropusamvinna.is/page/ies_Eyjafjallajokull_eruption
    Much bigger eruptions have occurred in the recent past. Pinatubo in 1991 spread ash around the globe between 20N and 10S well up into the stratosphere but flights were not prevented from crossing the equator. Between 1973 and 2003 there were 102 incidents between volcanic ash and aircraft. No-one was injured. No plane ‘went down’. In fact, based on past experience, a descent to lower altitude has allowed damaged engines to be re-started.
    http://www.ofcm.gov/ICVAAS/presentations/s1–06guffanti.ppt
    If you feel nervous about flying with a bit of dust in the air perhaps you should remember that humans fly and maintain your aircraft and they are statistically much more dangerous than volcanic ash.

  62. Does this means that every flight that would normally fly above inactive and near active volcanoes should be changed outside a certain “safety” zone around them, you know… just to be safe? I don’t know how planes could fly in certain parts of the world if they aver do that. They often divert flights around big thunderstorms… just in case!
    The society has become so disconnected from reality and so afraid of the reality of death that it is starting to cost to the economy. It might not be surprising that we are willing to spend septillions (10^24) of dollars to fix a non-problem (i.e. global warming).
    In the present, the precautionary principal would recommend flight diversions, not cancellation.

  63. Hu McCulloch (08:54:20) :
    If drone spy/attack planes work in Afghanistan, it should be possible to build a drone jet to fly through the cloud and see if there are any problems. Just 1 or 2 of these could stand by to cover any spot in the world.

    Yeah with a ceiling of 25,000 ft and a range of 400 miles that’ll work well. Iceland’s about 1000 miles from London, cover a swath 200 miles wide at all altitudes!

  64. Billy Liar (10:38:34) :
    (Required Minimum Navigation Performance – RMNP)
    should read:
    (Reduced Vertical Separation Minimum -RVSM)

  65. Eduardo Ferreyra (10:38:06) :
    stevengoddard (10:05:38):
    Eduardo Ferreyra (09:54:00) :
    I used to fly from SFO to London on a regular basis. The eastbound flights go over southern Greenland and pass just south of Iceland. Sometimes the westbound flights travel right over Iceland.
    * * * * * * * * * * * * * * * * * *
    Steven, were your flight non stop, or had a stop over in the East Coast? Because transpolar flight are quite common.

    Here’s the great circle route london to seattle.
    http://www.gcmap.com/mapui?P=lhr-sea
    Similarly for the route to SFO both would have you flying along the axis of the plume!

  66. Well, I’ll disagree. This shows the fallacy of relying on MET computer models and of letting the EU government dictate behaviour from on high. The post is based on several assumptions that don’t stand up to scrutiny. For one thing, it seems to ignore the existence of radio.
    There is an element of truth, however, in that the MET has been unfairly accused of ordering the flight ban, and the post addresses that issue fairly. Overall, a good post, well “worth blogging about.”

  67. The Met Office reported actual ash data and provided predictions on how the ash cloud would change. Observations showed their model predictions were quite accurate.
    What the aviation authorities choose to do with that data, and predictions, is up to them.
    The MetO came out of this rather well. Shame the same can’t be said of the airline industry who created the problem by failing to conduct tests to determine safe operating limits.

  68. 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.

  69. Eduardo Ferreyra (10:38:06) :
    Nonstop. I used to take the BA SFO -> LHR flight every few weeks, and they are equipped with a GPS TV station so you always knew exactly where you were.

  70. 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.

  71. There is a lot of dicussion around the computer models not being skillful. This is important if the models are used for making important decisions. The problem as I see it is that most people tend to focus on the lack of ash where flights are cancelled. This is understandable, people get upset when stuck for five days, as I have been, if the models are wrong about ash that is not there.
    Everyone claims that safety is more important than anything else. I think this is wrong. If safety was the most important thing when taking decisions where to fly, then the models should be forced to show that when they say there is NO ash, then there should be no ash, Think about it, if the models say that there is ash in Denmark but not in Sweden, grounding planes in Denmark is a no brainer if safety is your only concern, but to continue to fly in nearby Sweden should be a headace. How good are these models to avoid false negatives should be the most important question if safety is the major concern, but that discussion is not found anywhere.

  72. 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.

  73. Billy Liar (11:02:44) :
    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!

    And it isn’t the military one used in Afghanistan. How long to take it to it’s destination and set up a search pattern to adequately cover the expected plume, and how many are you prepared to lose due to engine failure?
    About 30% of predators are lost in Afghanistan due to icing issues.

  74. 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.

  75. UBS (11:19:06) :
    Rubbish! Air traffic control is usually managed chaos. If everthing changes it’s still managed chaos. The risk of collisions is always the same – someone has to make a mistake for the risk to arise.
    How do you think they cope when major thunderstorms occur in the summer in the continental US?

  76. 1DandyTroll (11:16:58) :
    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 shortest route between two points on the earth is a great circle, certain map projections are used for navigation because a straight line on the map is a great circle! (Gnomonic)
    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.

    All longer routes probably requiring stops.
    Met Office ought to be sued back down to earth.
    Yeah sued for doing their job properly which would result in shutting down all the world’s VAAC systems thereby blinding all air traffic to such events!
    That’s really smart.

  77. 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?

  78. Everyone claims that safety is more important than anything else. I think this is wrong.

    It’s definitely wrong. If safety was more important than anything else, then we should never fly again since there are always risks involved with flying. However, the risks involved with flying are obviously acceptable given the benefits of flying.
    I also need to ask about the number of deaths which resulted from the increased number of travelers that decided to drive to their destinations. It’s long been established that highway driving causes more deaths than flying. Increasing the number of highway drivers causes increased deaths. Therefore, the ground of aircraft caused deaths.
    I want to know the number of deaths this has caused.

  79. 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…

  80. One would think one would check figures before making a post like this. A number of airliners have ranges in excess of 7000 miles, sufficient to fly New York to London, circle Heathrow a few times and fly back with adequate reserves. Flying out to Iceland and turning around would have been a problem for Lindbergh in 1927 but a lot has changed since then.

  81. 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?

  82. Los Angeles county goes up in flames every few years and I remember watching the fires on the ground as I descended into LAX. I don’t recall any flights being grounded because of the fires but I’m sure the fires produced sufficient updraft to put lots of particulates into the air. Enough so that I had ash in my driveway 10 to 20 miles from the fires. So not all ash is equal. And the heavier most damaging components of volcanic ash will fall out of the sky much much faster than the lighter, smaller particles and water vapor from the eruptions.
    And I think that is part of the problem of the MET models. They are designed to model how water vapor and gas move around the planet, not the sandy, engine destroying components of volcanic ash. They will give a good idea of where to look for them but will tell us nothing about how much is actually still left in the atmosphere.

  83. I’ll repost something I posted yesterday:
    First, it’s unlikely — I dare say impossible — that an airplane would crash from flying through light (undetectable by satellite) ash. (There have been no crashes from flying through even the heart of heavy plumes, despite some flame-outs.) The worst would have been a need for earlier maintenance on the engine. That trade-off should be the airline’s call to make.
    Second, I don’t think it was necessary to prohibit flights over areas far away from the potential cloud, like Spain, at such an early date as was done. Whoever was responsible was exhibiting hall monitor behavior (jack-in-office officiousness).
    Third, the real scandal was the failure to do pro-active and coordinated contingency planning, despite having a month’s advance warning. Hopefully, that planning will now occur.
    Fourth, a long-range ash-cloud-monitoring drone/UAV should be designed that can fly through ash (maybe using the old V1 bladeless design) and report on its characteristics in real time, and fleets of them should be deployed in volcanic hotspots on heavily traveled airline routes. The cost/benefit ratio would be attractive, even if the project costs over 100 million $.
    PS: Ash-testing drones could take off from Iceland and land downwind in Scotland, Scandinavia, SE England, Germany, etc., etc. There they’d be refueled and head back to Iceland (or wherever they were needed most). Their range wouldn’t be cut in half by a need to return to a home base, IOW.

  84. Steven
    It’s only upwind because of the positions weather systems. It actually went south south east, initially. Visibility at London airports in late april is normally very good. Visibility in artic air is very good if it isn’t snowing. The difference with this eruption is that it happened within 3000km of the nuttiest governmental regimes in the world. Europe and GB.

  85. 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.

  86. I find that people that compain about air travel, airports, flight delays and airport security do not actually travel much. They also seem to use the term ‘small world’, which is a total joke if you actually have to move around it much, believe me it is actually a very big ball, in places it is over 5 movies wide.
    However if the models were right in saying the air was not safe, and the air has not changed, then why is it safe now?
    Why did they not simply say, “We do not know if it is safe to fly right now so we are going to check, please wait.” Then actually check the real conditions with real instruments on real planes and baloons for a day or two. Then say “OK we have checked, it looks OK, thanks for waiting” or “No, it looks bad, you need to keep waiting, we will check again tomorrow”
    Honestly goes a long way with passengers.

  87. stevengoddard (08:56:50) :
    And you need to continue to be a big fan of fusion for at east another 35 years and beyond. It’s still a fairy tale. Perhaps you need to keep your feet firmly on the ground rather than walking on clouds in the sky.

  88. 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.

  89. Not sure!
    I have lived under where the Met office model said the ash cloud was for 6 days.
    I only observed any evidence of ash on one day (the first day) when a very light dusting was on my car.
    All other days the sky was remarkably clear, clearer than normal for UK, wherever I went in UK .
    So the first day the model was maybe correct, but why didn’t they look out the window, and travel about a bit?

  90. >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?

  91. Billy Liar (11:29:17) : yes, but there is a difference when you have experience handling storms and know alternatives, this volcano is no such thing, it is a “first”

  92. 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.

  93. Steve,
    Why comment an something you clearly know nothing about?
    This is as bad as climate scientists predicting thermageddon.
    The precautionary argument is not a valid one. We take risks all the time. A pilot can decide to change course or change altitude, this is why there are pilots in the plane rather than computers. Is someone suggesting there was heavy ash (enough to bring down a plane) everywhere across all of Europe – I don’t think so.
    It is ever so obvious that the draconian government no-fly measures were overdone otherwise planes would have fallen out of the sky everywhere once flights resumed.

  94. 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…

  95. David Porter (13:15:00) :
    “U.S. consumers reduced their air travel by between 12 and 20% in the 3 months after 9/11”
    http://www.medicalnewstoday.com/articles/41573.php
    “In 2001, the winter-flu season developed more gradually than usual in the United States because of a reduction in air travel after the Sept. 11 terrorist attacks, a new study says. ”
    http://www.highbeam.com/doc/1G1-151900499.html
    It was great travelling to Europe back then. I would frequently have an entire row to myself and could put the arm rests up and sleep.

  96. 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.

  97. Ian W (12:32:18) :
    I don’t know if anyone will read this far… but here are the issues:
    _______________________________________________________________________________
    Very well stated. However I would like to add one very crucial point. As we see government “consolidation” and “harmonization” of laws across international borders. As we see international bodies like the World Trade Organization and the United Nations take the dominate role over supposed sovereign nations this type of bureaucratic bumbling will increase.
    Britain’s 2001 Foot and Mouth epidemic was a classic example.
    “….It is difficult not to conclude that the handling of the 2001 foot-and-mouth crisis amounted to an act of maladministration as grave as any for which a British government has ever been responsible….
    As one of the greatest social and financial disasters ever to fall on peacetime Britain, it was hardly surprising that for months there had been calls for a full public inquiry into every aspect of how the Government had handled the great foot-and-mouth crisis of 2001.

    …senior veterinary scientists outside the UK were all-but unanimous that it was too late for a policy based exclusively on slaughter to contain the spread of the disease. The only way to eradicate it was to use ring-vaccination round the outside of the areas where it had been identified, gradually working into the centre of each area.
    If such a vaccination programme had been efficiently organised, experts like Professor Brown and Dr Barteling insisted, the epidemic could have been brought completely under control in a matter of weeks, and at minimal cost….
    The next problem was that a combination of two factors conspired to stop this happening. The first was the historical British prejudice against use of vaccination for foot-and-mouth. The second was that the European Commission made clear that it would strongly oppose any widespread use of vaccination in Britain, because this might endanger the international trading status of the entire European Union. There are still large potential export markets, as in North America and Japan, which prohibit imports of meat products from countries which use vaccination against FMD. …IIn this respect, of course, an anomaly arose when Holland applied to Brussels to carry out a limited vaccination programme in April. So insistent on vaccinating were the Dutch that their permission was granted, they were entirely successful in halting the epidemic and, having insisted on slaughtering the vaccinated animals, they recovered their full export status only four months later, in August. For some reason this was not considered to affect the trading status of the rest of the EU….”

    This account is well worth the read for the lessons taught about large bureaucracies such as the EU, the UN, and WTO. Since this type of multilevel bureaucratic fiasco is going to be the “wave of the future” if Maurice Strong, AL Gore and their globalist buddies have their way.

  98. 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.

  99. stevengoddard (12:52:53) :
    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.

    The 767 is also a twin-engine aircraft. This increase the risk potential over a 4-engine jet such as the 747.

  100. I’d say stevengoddard doesn’t have much of a clue about air traffic control, aviation operations, the size of the sky over the North Atlantic, the very dim prospects for practical fusion power from ITER and perhaps about much else. I’m going to ignore his posts in future.
    If we want cheap, nearly unlimited energy for at least the next few thousand years fission is here right now and will do the job. ITER is just a Euro jobs program as that benighted continent sinks into a morass of over regulation and a version of the “permit raj”. I’m still hoping Doc Bussard’s ideas work out though.

  101. stevengoddard (12:52:53) :
    Not a lot of room for error.

    On the contrary, the fuel is quite adequate for the full route, and alternates for emergency refueling are readily available with small fractions of the remaining fuel.
    Your Great Circle route is not an accurate representation for all or even most of the SEA-LHR, LHR-SEA, SFO-LHR, LHR-SFO, LAX-LHR, LHR-LAX flights. There are a number of different jet routes in use for thos departure-destination routes. The eastbound flights tend to use the more southern routes passing over and south of Iceland at lower altitudes to save fuel by riding along with the highspeed winds inside the jetstream. The westbound flights avoid the headwinds in the jetstream by flying farther northwards in some cases and flying at higher flight levels above the westbound headwinds. My commercial flights between Los Angeles, Seattle, and London most often crossed the Atlantic Ocean with Iceland far away on the southern horizon or nearby to the south of the flight path. My westbound flights sometimes used the jet routes across Central Greenland, the Canadian Northwest Territories, Yukon, Vancouver, Seattle, San Francisco, Santa Barbara, Los Angeles. Other flights crossed Central Greenland, Northwest Territories, Alberta, Montana, Reno, Central California, Los Angeles. The routes varied according to upper level winds and many other factors. We flew slightly west of Mount St. Helens as it continued to smoke some weeks after the big eruption.
    Although flying into volcanic ash plumes is not recommneded for reasons of passenger safety and economy of aircraft maintenance, especially for commercial aviation, The widescale and arbitrary shutdown of European airspace by whomever appears to be unwarranted by past applications of ICAO and other flight regulations and experience. It may even be fair to characterize the scope of the flight restrictions as unprecedented for volcanic ash hazards and arguably an hysterical overdone response to a relatively minor risk.
    While the Met Office is not directly responsible for making the decisions which shutdown European airspace, the Met Office is directly responsible for the accuracy and inaccuracy of its observation programmes and its forecast models used by the decisonmakers. To the extent of which the Met Office and its supporters in the executive and legislative branches of government are responsible for any lack of an effective observational programme capable of providing real world data on Icelandic volcanic ash presenting risks to flight operations, they are then also culpable for any over reliance upon unreal computer models by the decisionmakers. Consequently, the Met Office computer modeling is a legitimate topic of political debate insofar as those computer models are used to supplant the proper usage of accurate real world observational data by the decisionmakers.

  102. 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.

  103. The accepted standards are that if the ash cloud is not visible to the naked eye and not visible from space it is not a major threat to aircraft. All that needed to happen in European airspace was setting up an exclusion zone around the volcano and flying VFR rather than IFR elsewhere – ie no flights at night and no flying through clouds – with air traffic controllers directing aircraft around or under the *visible* extent of the ash cloud.
    The Met Office predictions *were not* as accurate as some are claiming given that the first flight they sent up to find the cloud wasn’t able to.
    It wasn’t the job of the Met Office to close the airspace but the data they were feeding NATS and the CAA does appear to have been inadequate until they got BAe-146 G-LUXE back into service.

  104. 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.

  105. Being some 9500 km from home at the moment and seeing this all happen from within Japan the initial decision to ground flights was a good one.
    Where the EU failed big time was in follow up test to verify if the ash-clouds did pose a serious threat to airplanes and the insanely slow process in wich EU-ministers has to come to a decision in opening the skies again. They wasted a whole weekend before they started talking again on monday.
    Flights could have been resumed at least 2 to 3 days earlier.

  106. 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.

  107. @ Symon (08:36:47) :”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.”
    In addition to Greenland, there’s Keflavík (KEF) in Iceland. There was a time not long ago when we needed these refueling stops for heavy bombers and fighters traveling to the European war zone.

  108. 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.
    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?

    Transatlantic reroutes happen all the time for unpredictable weather.
    Dodging hundreds of high speed bullets isn’t all that hard if
    a). they’re in several hundred thousand cubic miles of airspace
    b). you see them minutes ahead of of time
    c). they’re trying to dodge you, too
    Transatlantic paths don’t cross. What may look close would be an aircraft at a different altitude, and the pilots would be well aware of it, both visually and electronically.
    International flight rules require planes to have alternate airports all along the route, and plenty of gas to get to them, and then diddle around for an hour or more before landing.

  109. For once I tend to agree with Steven. Let’s put this whole thing into perspective. In 2008 the European Airline industry had operating revenues somewhat above $160 billion (see http://www.atwonline.com/channels/dataAirlineEconomics/World_Airline_Report_2008.pdf). Actually, revenues are probably significantly more, as I only included the major airlines in my total.
    Even if regulators had not implemented a flight ban, many airlines would have cut some flights due to the risks of equipment damage, airline reputation, law suits and so on in the event of an accident. Therefore, the Volcano would likely have still cost the industry somewhere in the vicinity of $500 million to $1 billion. Thus, the regulators are at most responsible for $1-1.5billion in losses, which is still well below 1% of the total industry annual revenue.
    Could the regulators have been more responsive and reduced some of the losses? Sure, but this whole argument is really a tempest in a teapot, probably stirred up by the Airline industry to siphon off more money from the government and pad their bottom line. I’m sure there are plenty of other regulatory blunders happening all of the time in the airline industry accounting for more than a 1% drop in revenues. There are probably also benefits greater than 1% of revenues that the airlines get from the bureaucracy, such as public assistance in funding Airports, Airport security, Air traffic control, etc…
    The bottom line is that from a purely financial perspective this is a minor blip and if we look at it rationally should have been lost in the noise.

  110. 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!

  111. Lots of experts posting here who know more about my experiences than I do.
    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.
    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.

  112. “Erupting volcanoes can change in the blink of an eye, as people near Seattle found out at 8:32 AM on May 18, 1980. ”
    Non erupting volcanoes can do the very same thing. We should ground ALL flights. While it is nice and wonderful to say that safety is first, what was first is that they spent 5 or 6 days without sending any actual test equipment up to see what the reality was and based the entire grounding on computer models. You cannot possibly condone that sort of action can you? Grounding the planes for a day or two while they launched weather balloons and used storm chaser aircraft to actually see what was going on I could see as safety, after that it is negligence.

  113. Symon (16:56:44) :
    I’ve taken that drive many times. Even the cops are stoned. I once exited at Scotts Valley with an overheated radiator and three small kids in the back of the car.
    A cop spotted me not wearing my seat belt and followed me into the gas station, where I explained the situation. After he wrote the ticket and was walking away, I got out of the car to go buy some coolant. He pulled his gun and demanded to know where I was going. I told him I was going to “buy some coolant.” He thought that over for a minute and then gave me the all clear.

  114. 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.

  115. I disagree.
    Flights are rerouted all the time in the USA due to severe weather. Pilots, dispatchers, and the FAA work hand in hand to deal with the issues as they arise. Often storms bloom around Miami long after the flights have left Seattle. Planes will divert if they run low on fuel. It is called operations and the airlines are very good at it.
    All flights are required to have PET or Point of Equal Time destinations all along their route. These are other locations they can divert to. Looking at the polar route you drew, the flight can divert around Iceland opposite the plume location to Scandinavia/Ireland, Russia, land in Iceland, or turn back and land in Canada. Or Greenland. Or, they can climb to a higher altitude or a lower one.
    Flights are also required to maintain fuel reserves that are the worst-case scenario to finish the flight, ie flying at 10,000 feet with a headwind and having to circle in a pattern before landing.

  116. Volcanic Dust????
    UK south west 3 weeks unwashed!
    http://img541.imageshack.us/img541/3530/volcanicdust.jpg
    Note the new layer on the window
    Many cars exhibit this fine buff colored dust. In sunlight there are reflective bits visible.
    Is it volcanic origin?
    any way of telling?
    If volcanic then the dust is not all above 16000ft. Planes fly through many layers on take off.
    Engines suck a lot more air that a windscreen! turbine blades are cooled by through flow air. Turbine blades reach temperatures where glassification can occur.
    cooling channels closed by glassified dust will lead to overheat and EVENTUAL failure (see the NASA experience)
    There have been few eruptions in european crowded airspace. This may be the first example?
    Planes cannot detect dust with radar (it is tuned for water molecules)
    Planes cannot therefore steer around a cloud. They would have to use the info from the met models. These have been claimed to be inaccurate!
    The met office predicts the path and height.
    The met office does not say it is unsafe to fly.
    The met office does not fly planes to test the dust cloud.
    Who wants 400 deaths on their conscience

  117. 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.

  118. stevengoddard (17:49:48)
    You write that the Met Office did no wrong. What did they do right?
    They failed to communicate the urgent need for measurements to verify the models’ outputs by making the users of the information aware of the limitations of the models.
    Diversions around clouds don’t mean necessarily taking a 180 degree turn. If they could not get to Heathrow, then there would have been a fair number of other options on the European continent even 6 hours after the eruption; unless the *authorities* shut down all the airports because they don’t fully understand what the VAAC London (Met Office) is telling them; nor understand and take responsibility for the consequences of needlessly shutting down airspace.
    Airlines and aircraft manufacturers also contributed to the fiasco. They allowed the zero-tolerance myth to propagate into regulation. They’ve certainly had 20 years of flying jets through ash clouds from which to draw some idea of what constitutes acceptable and catastrophic exposure. They should have been requesting estimates and subsequent measurements to confirm ash concentration levels from VAACs based on exposure and risk criteria.
    IIRC, manufacturers now specify 2000 ppm as (commercially?) acceptable, presumably indefinite exposure. Which is infinitely more than that which was ASSUMED acceptable by Eurocontrol. “No specified level” of exposure isn’t the same as zero.

  119. Seems very simple for the Icelandic government (oops – maybe that’s a bad assumption….) to fly one weather balloon (with GPS, battery, radio location transponder, and height-ballast drop controller-ballast bag) from the volcano site each day, one balloon every six hours until the ash plume ceases.
    Cost? Once the prototype is built: less than 2500.00 per balloon and transponder set.
    Balloon (by definition) flies the same route at the same wind speed as the plume at that height, as long as the ballast controller and height (altimeter) device remain charged. You need one low altitude, 2 at assumed plume height, and 1 aobve the plume height.
    Go high-tech – One every other day, add a filter and fan moter to see actually how much dust is present.
    Now you know where the plume is. You avoid the plume.
    End of “model” assumptions. End of hysteria by the Met Office (defeinding their models) and the bureaucratic control by the unknown bureaucrats in the EU anonymous halls of anonymous government control.

  120. 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?

  121. stevengoddard (19:21:30) :
    Another SEA-LHR aviation route map, identical to the one in this article.
    http://avise1.com/route-map/

    You don’t understand, those are Great Circle “service” route maps. They do not represent actual flight paths used in flight planning and navigation. To get the concept across, think of the Great Circle route maps as analogous to the graphic used in a road atlas to represent the relative distances between cities without representing the actual highways and roads used to physically travel between the cities.
    To see where an aircraft’s actual flight path is in relation to the Great Circle route, start with a jet navigation chart (JNC) and have a commerical flight crew draw their actual flight paths for you on the JNC.

  122. 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.

  123. From Nasa document:
    SUMMARY
    In the early morning hours of February 28, 2000, the National Aeronautics and Space Administration
    (NASA) DC-8 Airborne Sciences research airplane inadvertently flew through a diffuse plume of
    volcanic ash from the Mt. Hekla volcano. There were no indications to the flight crew, but sensitive
    onboard instruments detected the 35-hr-old ash plume. Upon landing there was no visible damage to the
    airplane or engine first-stage fan blades; later borescope inspection of the engines revealed clogged
    turbine cooling air passages. The engines were removed and overhauled at a cost of $3.2 million. Satellite
    data analysis of the volcanic ash plume trajectory indicated the ash plume had been transported further
    north than predicted by atmospheric effects. Analysis of the ash particles collected in cabin air heat
    exchanger filters showed strong evidence of volcanic ash, most of which may have been ice-coated (and
    therefore less damaging to the airplane) at the time of the encounter. Engine operating temperatures at the
    time of the encounter were sufficiently high to cause melting and fusing of ash on and inside
    high-pressure turbine blade cooling passages. There was no evidence of engine damage in the engine
    trending results, but some of the turbine blades had been operating partially uncooled and may have had a
    remaining lifetime of as little as 100 hr. There are currently no fully reliable methods available to flight
    crews to detect the presence of a diffuse, yet potentially damaging volcanic ash cloud.

    A seven minute flight through a dust cloud further north than UNEXPECTED = $3.2M
    And what is worse not easily seen damage that reduced the engine life to 100hrs

  124. 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!

  125. 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.

  126. 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.

  127. http://www.google.com/hostednews/ap/article/ALeqM5jAf1iuo3kzP9oGbVLbZwP68iCFpwD9F89IUO0

    US military fears volcano could harm jets
    By ERIC TALMADGE (AP) – 11 hours ago
    RAF LAKENHEATH, England — U.S. Air Force officials warned Thursday their biggest fighter wing in Europe could suffer long-term damage if Iceland’s volcano keeps belching ash into the skies.
    The Air Force sent two F-15 fighters on test flights Wednesday and another eight on Thursday, but said not enough data has been gathered to resume normal operations, despite the lifting of the civilian flight ban and the return to the skies of commercial airliners.
    Col. John Quintas, an F-15 pilot who commands the 48th Operations Group, said the test flights all returned safely after about 75 minutes in the air. The fighters did not encounter any major problems, though some pilots reported haze in areas that were deemed the highest risk.
    “They certainly didn’t come down clean, but they did come down safe for flight,” he said.
    He said mechanics were analyzing the fighter engines to determine the extent of the impact of the ash, but added that determining their safety would be a complex task because the risks might not be immediate.
    “What we are concerned about is the long-term effects of low-level exposure,” he told The Associated Press at RAF Lakenheath, an Air Force base about 80 miles (100 kilometers) northeast of London. Lakenheath’s 82 F-15s make it the largest U.S. fighter base in Europe.
    Normally, about 50-60 fighters take off on missions from the base each day. On Thursday, only the eight test flights were allowed.
    “We are in uncharted territory,” Quintas said. “We could be in this situation for months.”
    The safety of the military fighters has been watched as an indicator of whether commercial airliners should be allowed to fly and the first forays were not good — test flights by a Belgian F-16 and two Finnish F-18s over the weekend, before the civilian ban was lifted, resulted in minor engine damage.

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

    In one incident, all four engines of British Airways flight shut down when flying though the ash of an Indonesian eruption in 1982. The same thing occurred in 1989 when a KLM jet flew through a cloud of ash in Alaska. Both flights were able to restart their engines, but only after losing more than 10,000 feet of altitude.
    “Even when you set aside things like potential law suits from loss of life, and things like that, the damage to the plane by flying through the ash can run into tens of millions of dollars,” says Benjamin Edwards, a volcanologist at Dickinson College in Carlisle, Pa.
    KLM, for example, had to replace all four engines on the aircraft, which was less than a year old, at a cost of $80 million.

  129. 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.

  130. NickB. (08:22:25) :
    3.) A big part of the complaint is that the MET almost, if not completely, exclusively used computer models to predict dispersion. They also appear to have gone off of a zero tolerance policy. Without confirmation by real measurement, there was no way to tell if the risk was even real or just the figment of a computer’s imagination.

    As a former NBC NCO, one of my responsibilities was to predict fallout patterns from nuclear yields and fallout has a lot of similarities to volcanic ash. These predictions can be fiendishly difficult as the particles fall through the atmosphere and encounter varying winds speeds and directions at different altitudes. 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 you are outside the predicted zones you’re almost certainly in a clean area, but if you’re inside the predicted zone it’s defiantly YMMV, your mileage may vary. The prediction is always intended as a starting point, to be replace by actual surveys of the existing situation. If it’s such a financial hardship for the airlines to be grounded for safe-sided ash predictions, they should get some aircraft modified to safely survey the ash clouds.

  131. 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.

  132. Volcanic eruptions are not all that common. Closing for 1 week for safety concerns does not seem all that bad a decision. In hindsight, in light of the test flights, perhaps alternatives to a complete flight ban could have been made, eg certain longer routes to the same destination, albeit requiring longer flight times might have been permitted, but for logistical reasons, the airlines might have stayed grounded anyways.
    BTW, I wonder of those test flights through the ash are insured. Losing a plane without any passengers is probably cheaper than losing 1 with 400 passengers. Perhaps the data will help the models in the future.

  133. http://volcanoes.usgs.gov/ash/properties.html
    Are there any pictures of damaged blades from those two incidents?
    Realtime advice via radio should be able to warn pilots who are on track to
    pass within a specific distance from the ash plume.
    See link above for particulate size in relation to distance down wind from volcano.

  134. 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.

  135. I agree with most of what Steve Goddard says, but he has entirely missed the point.
    The Met Office was not responsible for closing UK airspace. That was the decision of the CAA, the Civil Aviation Authority.
    The role of the Met Office was simply to provide forecasts to guide the CAA in their decision.
    The original article suggested that the Met Office’s forecasts were inaccurate, based on flawed computer models. If that is so, then the Met Office deserves criticism. Its responsibility is to provide the best information possible.
    In this case it may be that inaccuracy caused us to err on the cautious side, but we cannot be sure it will always work that way.

  136. 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

  137. Can people stop talking about a ‘dust cloud’? There was no cloud over Europe. A cloud is visible. The skies were perfectly clear. Planes should not fly through an ash cloud obviously but where is the safe distance fron the visible cloud [of ash not steam]?
    All this was about was a computer model of traces of ash over europe. The argument is about how much of a trace there was. The authorities went with a zero tolerance, a total over reaction.
    We are limited by the technology. When technology advances we will be able to ban flights over huge areas every time a small volcano goes off because it is detectable. Just think of the precedent this sets?
    I live over a 1000 miles from the eruption in southern England and our airports were closed – why? This was more than an over reaction it was an embarassing decision based on nothing more than ‘covering your arse’
    Many planes have flown though slight traces of ash without the slightest problem, historically [they must have as we had no supercomputers to tell them it was dangerous].
    cheers David

  138. >>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.

  139. Again, I want to know the number of highway related deaths that were caused because of the grounded aircraft.
    Decreased air travel = Increased highway travel = Increased deaths

  140. >>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.

  141. stevengoddard (17:00:13) :
    Lots of experts posting here who know more about my experiences than I do.
    Here is the flight path from SEA-LHR . . .

    That “flight path” from “Great Circle Mapper” is not what real airlines use. Here’s the quote from the top of the page, “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.
    Over-the-arctic routes are a bit different, of course, but Wikipedia has an accurate description of the North Atlantic Track System, which carries the huge majority of passengers between North America and Europe.
    http://en.wikipedia.org/wiki/North_Atlantic_Tracks
    The tracks vary each day, sliding up and down to follow the winds, but they all run parallel 60nm (1 deg latitude) apart with 10 minute spacing between aircraft – that’s about 100 miles. Westbound tracks run more northerly to avoid the winds.
    Vertical spacing is 1000 ft, which would look close. If you had a near miss, the report from the traffic controller and both aircraft would be in the system.

  142. 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.

  143. A German radio program reported on monday this week, that the European Union had a announced to provide compensatory payments to all air carriers who suffered from the European no-fly zone, except to those who already had been in financial difficulties before.

  144. 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.

  145. 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.

  146. 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.

  147. MJK,
    You speak as if action on climate is without uncertainties and risks. This is the kind of simple minded rhetoric that gets you warmies into trouble time after time. Unemployment is a leading cause of suicide, for one of many.

  148. 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.

  149. wobble (00:33:36) :
    That was one of the most impressive straw man posts I have seen yet. You aren’t even remotely addressing any of the issues in the article.
    You aren’t discussing volcanoes, ash, the inability to predict or detect ash at night, the uncertainty about short and long term effects of ash, the decision making process, the timeline of that process, etc.
    You have instead attached your argument to an incorrect claim that airplane GPS maps aren’t accurate.

  150. 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.

  151. Surely the whole point is that the met office relied on a completely theoretical computer model that was based on much denser clouds of ash and was not able quantify the changing density of ash clouds as they disperse.
    On top of this there was apparently no real capability of real time sampling of the clouds and feeding this live data back into the model.
    What other computer models are the met office famous for ?

  152. 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.

  153. Anders Valland (01:36:28) :
    The particulars of the ash from any given eruption can not predicted. This volcano hasn’t erupted for decades. There was no historical information to go by.

  154. 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.

  155. An airport wanting to service 400 jumbo jets would need more than ten square miles of parking space for the planes, and over 20,000,000 gallons of jet fuel.

  156. 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.

  157. stevengoddard (06:28:18) :
    Neither the military nor NASA are convinced that the ash levels are safe.

    That’s not the point. The point is whether or not agency have been honest about what they do and don’t know.

    An ash cloud can not be picked up by radar, and that is exactly why they had to rely on computer models.

    Actually, no, they didn’t have to rely on computer models which were rendered useless since they were based on dozens of overly conservative assumptions. The modelers should have simply been honest about what they didn’t know.

  158. 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

  159. @Phil
    ‘All longer routes probably requiring stops.’
    Uhm and having planes grounded earns you how much money?
    ‘Yeah sued for doing their job properly which would result in shutting down all the world’s VAAC systems thereby blinding all air traffic to such events!
    That’s really smart.’
    Where in lies the logic that just because Met-office get sued they’d have to shut down anything? Met-Office is an official entity of the UK gov. there by assuring nothing would be shut down. but it would assure that the information coming from Met-Office would be more sound and reliable in the future, and that is really smart.

  160. wobble (08:32:19) :
    What mechanism do you suggest for determining ash cloud extent and density during the night, when almost all the eastbound long haul flights pass Iceland?

  161. 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.

  162. stevengoddard (10:30:37) :
    What mechanism do you suggest for determining ash cloud extent and density during the night, when almost all the eastbound long haul flights pass Iceland?

    None, if none are accurate.
    That’s my point.
    And I also condemn the practice of claiming that models infused with overly conservative assumptions are accurate.

  163. stevengoddard (10:30:37) :
    wobble (08:32:19) :
    What mechanism do you suggest for determining ash cloud extent and density during the night, when almost all the eastbound long haul flights pass Iceland?

    Did you not read and understand the information in the link I provided. The GOES-R satellites for one example….

  164. 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.

  165. D. Patterson (12:07:50) :
    Looks like you didn’t read the link you provided. That imagery is not available for Europe and only works if there is no cloud cover.
    Also, the article specifically said GOES-West and not GOES-East. But neither satellite covers Europe.
    One million people a week pass through LHR. Are you going to bet their lives on your theories?

  166. 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.

  167. Steve,
    I have several hundred thousand miles of flying, my first commercial flight was in 1968 from Europe to the USA, as time has progressed so has ”safety” 99% of the ”safety” problems arise from legislators who ‘think’ they know best for a very specialized industry, and have never got off the ground to see how the real thing operates, most have watched the Hollywood version, you know lets scare em to death another time with a airline movie.
    I am a married man, with children and grandchildren, when flying a plane I know that all those people behind me have friends and families just like me, I like my life, the airlines and the industry has it rules and regulations which left alone work very well, but when you mix incompetence and politics you get a round hole with a square peg, flying (statistics show) is the safest way to travel, and that includes walking to the corner store, I do not know anybody (apart from terrorists) who work in this industry who would think for one second to do something outside the AIRLINES RULES AND REGULATIONS.
    PS all aircraft carry enough fuel to get the pilot home.

  168. 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?”

  169. stevengoddard (12:30:29) :
    The decision makers have to plan based on the longest flights.

    That’s an absurd assertion.
    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). Aircraft/flights which can’t plan to arrive in London with the required amount of fuel are restricted from initiating a flight. This would have allowed the airlines to make a business decision based on the requirement to carry extra fuel for the limited number of flights which could meet the minimum requirements.
    Now, before you misrepresent my point again. I’m merely saying that this is simply one example of the types of options which are available to the decision makers – despite your claims to the contrary. I’m not, repeat, not claiming that this would have been the correct decision.

  170. 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.

  171. wobble (13:03:52) :
    Six days is not a very long time to come up with a set of procedures for dealing with a new paradigm. Flights in Europe are back to 100%. They were appropriately conservative.
    But if Katla erupts, the whole thing is coming to a halt.

  172. 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.

  173. stevengoddard (13:28:35) :
    Six days is not a very long time to come up with a set of procedures for dealing with a new paradigm.

    What I suggested could have been decided and implemented within 6 hours.

    Flights in Europe are back to 100%. They were appropriately conservative.

    Was your first sentence supposed to somehow give credibility to your second sentence?
    Let me be clear, you failed to prove your case that “they” weren’t overly conservative.

  174. 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

  175. D. Patterson (13:30:53) :
    I don’t see that you are presenting any evidence that during the past week the Met Office did anything wrong. Had a plane gone down, there would have been plenty of evidence.
    Let us go “all the way” back to the first day of the shutdown, one week ago:
    http://wattsupwiththat.com/2010/04/15/ash-thursday-the-day-the-uk-was-planeless/

    The eruption of a volcano in Iceland has the skies over the UK and Europe filled with ash. Like what happened on 9/11 in the USA, planes are landing everywhere and staying out of the skies. Volcanic ash scours jet turbines, making in flight failure almost a certainty.

  176. 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.

  177. wobble (13:57:38) :
    A million people die every year around the world in automobile accidents.
    Society has deemed that as acceptable. Society considers one jetliner going down as unacceptable.

  178. 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.

  179. stevengoddard (14:14:54) :
    wobble (13:57:38) :
    A million people die every year around the world in automobile accidents.
    Society has deemed that as acceptable. Society considers one jetliner going down as unacceptable.

    I agree. One death on the road is an “accident”. One plane going down is hundreds of deaths and is a tragedy, and is unacceptable. (My own opinion is that all car “accidents” are unacceptable and I’ve never had one myself, but that’s only my personal experience).
    However, there is a level of risk that is acceptable when dealing with ash clouds, and we need to find that level. This volcano could well be spewing ash for months or years, and the same problem could crop up virtually anywhere at any time. We could go through a phase where Icelandic volcanoes spew ash for decades, and it would be insane to simply stop flying as a result.

  180. @stevengoddard
    ‘wobble (12:18:47) :
    The decision makers have to plan based on the longest flights. ‘
    From reading several comments from you to wobble it seems you don’t seem to understand that EU made a directive or rule, of protective measures, out of one single incident, that goes way further it seems than any other country, and even those countries directly afflicted by volcanos.
    The directive in itself is probably as sound as can bureaucratically be that doesn’t mean that it was followed correctly by Met-office. Do you know if Met-Office followed the rules correctly? How many measurements and readings did they take above Wales? Scotland? Ireland? Faroe Islands? France? Germany? Portugal? Spain? Denmark?
    And please spare us the logic of it being bad flying directly into an ash plume, that just makes the argument ludicrous.
    Met-office screwed up. They couldn’t shoulder the weight of the responsibility. And before you blow a fuse, answer this: Did they ever say they couldn’t shoulder the responsibility?

  181. stevengoddard (14:14:54) :
    A million people die every year around the world in automobile accidents.
    Society has deemed that as acceptable. Society considers one jetliner going down as unacceptable.

    Are you serious?
    Are you actually implying that it’s ok to have 1,000 extra highway deaths in order to prevent 90 aircraft deaths?
    Such implication is absurd.

  182. 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.

  183. 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

  184. 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..

  185. Oh, and one other thing. DTW, JFK, ATL, DIA, DFW and MIA put a lot more flights across the Atlantic than SEA, and all of their great circle routes go well south of Iceland.

  186. 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.

  187. Hey Skipper (17:47:54) :
    I fly from DIA->LHR all the time and the route passes close to Iceland, particularly on the return trip. Same story for San Diego, Los Angeles and Phoenix.

  188. 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.

  189. I fly from DIA->LHR all the time and the route passes close to Iceland.

    My dab — I meant to type IAD.

    Avoid the ash, land at an alternate airport, and drive back to the original destination?

    IMHO, a tough call.

    Actually, it isn’t.
    Every flight you go on is an example of managed risk: thunderstorms are a perfect example.
    The EU simply wiped out the managed part and treated risk as certainty. That is idiotic.

  190. Hey Skipper (18:44:27) :
    “Every flight you go on is an example of managed risk: thunderstorms are a perfect example.
    The EU simply wiped out the managed part and treated risk as certainty. That is idiotic.”
    ==========================
    You are flying into London with severe thunderstorms all over, but with no weather radar. Do you proceed, or wait for the storms to clear? Ground control radar is also blind.

  191. Hey Skipper (18:44:27) :
    Thunderstorms are discrete, visible, radar detectable and dangerous.
    Airborne basaltic volcanic ash is diffuse,generally invisible, variable in density, not detectable on radar and dangerous.

  192. stevengoddard (17:17:29) :
    If The Met Office gave the thumbs up…

    But Steven, Steven, Steven, Steven, here’s the question.
    Why did the Met Office need to give a thumbs down? Why couldn’t they have said that they lack the proper tools to provide an accurate assessment?

  193. u.k.(us) (17:56:31) :
    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.

    A tough call? No wonder your opinion is humble.
    Maybe you think we should ground all flights worldwide?!?!?
    After all, we never know if the destination airport weather will be better than approach minimums when the aircraft arrives?

  194. You are flying into London with severe thunderstorms all over, but with no weather radar. Do you proceed, or wait for the storms to clear? Ground control radar is also blind.

    I addressed that above. Aircraft do sometimes dispatch without operating weather radar. This is the quote from my aircraft’s minimum equipment list:

    Both [weather radars] may be inoperative provided flight is not released under IMC or night VMC when current weather reports indicate that
    thunderstorms or other potentially hazardous weather conditions that can be detected with airborne weather radar may be expected along
    route to be flown.

    In other words, the Mark 1 Mod 0 eyeball is a suitable substitute for weather radar when said eyeball can be effective.
    Ash clouds insufficiently dense to be seen are not a threat to aircraft safety.
    Therefore, during the day, in clear weather, precisely the same kind of risk management should have applied to the ash cloud as to convective weather. Instead, the EU tossed all those considerations overboard.
    NB: all the ash cloud run-ins you have heard about were the consequence of getting into unknown areas of high concentration.
    For the illustration at the top of this thread to be completely informative, it should include an overlay of the visible extent of the ash cloud and representative air routes across the Atlantic.

  195. u.k.(us) (18:27:46) :
    decisions were made, apparently by decision makers.

    The wrong people preempted the right decision makers by misrepresenting their confidence in ash plume forecasts.

  196. Hey Skipper (20:23:52) :
    Therefore, during the day, in clear weather, precisely the same kind of risk management should have applied to the ash cloud as to convective weather. Instead, the EU tossed all those considerations overboard.

    Hey, Hey Skipper, Steven Goddard thinks it would take too long to have implemented such procedures. I contend that such procedures could have been established within 6 hours. What do you think?

  197. Hey Skipper (20:25:52)
    Ash clouds insufficiently dense to be seen are not a threat to aircraft safety.
    Read the .pdf in http://ad.easa.europa.eu/ad/2010-17
    “Flight in airspace with low contamination of volcanic ash may have medium to long term consequences to aircraft safety.” Included are list of daily checks.

  198. Here is the official explanation from the CAA. Should clear up most of the nonsense that has been flying around this thread.
    http://www.telegraph.co.uk/news/worldnews/europe/iceland/7622520/Why-it-took-six-days-to-reopen-the-skies-after-the-volcano-erupted.html

    Why it took six days to reopen the skies after the volcano erupted
    Deirdre Hutton defends the CAA’s decisions and says it led the way in getting airlines flying again.
    By Deirdre Hutton
    Published: 7:09AM BST 23 Apr 2010
    The eruption of the Icelandic volcano led to six days which were unprecedented in aviation history. As the cloud of ash from Eyjafjallajökull drifted across Northern Europe, British airspace was closed for the first time – and remained shut until Tuesday night. So what happened in between? And why did we support NATS in taking such drastic action?
    When the news about the volcano broke, we at the Civil Aviation Authority were faced with a huge challenge. The unequivocal guidance from manufacturers – based on such events as the multiple engine failure that affected a British Airways flight in 1982 – is that aircraft encountering volcanic ash must “AVOID AVOID AVOID”, and make sure there is absolutely no interaction between jet engines and ash.
    This advice works well in the US, with its vast open spaces, where you can fly around any ash or re-route to alternative airports. In the UK, with its congested, highly complex airspace, and a blanket of ash spread across the whole country, neither option was possible. There was no guidance that would have allowed the regulator to keep airspace open with any assurance of safety – and we were only able to reopen the skies after an enormous effort, in which we brought together nearly 100 organisations around the world. Some critics have said that this took too long – but I would not have put my family on a flight until that assurance was given, and the public reaction suggests that the majority of passengers agree.
    The problem was enormous. First, we had to understand the extent of ash contamination, by sending up planes bearing instruments that could measure its density (complementing the data provided by ground-based lasers). Second, we had to work out which planes could safely fly through which parts of the continent’s sky. To do this, we and the leading manufacturers had to come up with new guidance on how aircraft could safely fly through slightly greater levels of ash. The CAA led the way across Europe.
    Behind the scenes, the efforts have been intensive. After the problem emerged on Thursday morning, the day was spent coming to grips with the scale of this challenge. Over the following five days, the CAA held continuous conferences with international and European regulators (notably the US’s FAA), as well as manufacturers and aviation experts. We collected as much data as we could, including having commercial jets, without passengers, follow our instrument-bearing planes. Before and after any flights, engines were intensively examined to check for any correlation between ash density and engine damage.
    By Monday, we had enough data for EU transport ministers to agree our proposed new zoning system, which established a no-fly zone where the ash was densest, a secondary zone where flying could be resumed (subject to the manufacturers’ approval and increased checks on the engines), and a tertiary, ash-free zone.
    By Tuesday afternoon, the key manufacturers had agreed that revising the guidelines would not compromise safety. Forty-five minutes later, the CAA board met in emergency session and agreed the new guidelines. Two hours after the meeting, we reopened the skies. The fact that British Airways had planes in the air played no part in our decision.
    Throughout this crisis, our key principle has been public safety. When dealing with people’s lives, an accumulation of anecdotes does not equate to scientific evidence.It’s entirely understandable that passengers and airlines don’t want an interruption to services. But we have to do what’s right for public safety – and will continue to do so.
    Dame Deirdre Hutton is chairman of the Civil Aviation Authority

  199. That report by Dame Diedre Hutton seems logical and reasonable. There is always a conflict between turbofan manufactures who have no ash tolerance and airlines who need to keep the cash flowing, the CAA acted well as a moderator.
    Another interesting comment from a pilot…..

    At best, I predict that operators are in for a torrid time covering wildly escalating turbine maintenance costs, quite apart from the downtime waiting for non-available spares.

    That should be quantifiable.

  200. Hey Skipper, Steven Goddard thinks it would take too long to have implemented such procedures. I contend that such procedures could have been established within 6 hours. What do you think?

    I lost track of precisely what procedures he is talking about, and I have to start getting ready to leave the hotel in few minutes, so I apologize in advance if I miss the point.
    Procedures already exist to divert around areas of severe weather, which, in principal, is no different than what we are talking about here.
    I think the UK made a good call initially to shutdown the airspace; however, because they essentially dumped the whole notion of risk management, it took way too long to get things going again.
    I must admit I wasn’t flying in Europe when the volcano popped, so I don’t know for sure what the concentrations were over the continent, but my impression is that they never amounted to anything.

    Read the .pdf in http://ad.easa.europa.eu/ad/2010-17
    “Flight in airspace with low contamination of volcanic ash may have medium to long term consequences to aircraft safety.” Included are list of daily checks.

    Thanks for the link; I did.
    Keep in mind that I was talking about air safety, not airworthiness. I know that sounds like I am repeating myself, but I’m not.
    By air safety, I mean that concentrations of ash too low to be visible will have no effect on the outcome of the flight.
    The link directs additional measures to ensure the aircraft’s airworthiness before the next flight: in essence they direct mechanics to do additional ground inspections to determine if there are any effects accruing but that have not yet affected normal ops.
    It is worth noting that many, if not most, airplanes (remember AF 447) automatically datalink all kinds of operating parameters throughout flight.
    Rolls Royce, for example, tells its customers when an engine needs work by the data linked to its ops center.

  201. stevengoddard (20:35:12) :
    Why? Because it is their job.

    That’s crap. It’s not the Met Office’s job to give a thumbs down about something they don’t know enough about and can’t predict.
    They should have simply said that they don’t know enough about it and can’t predict it.

  202. wobble (20:45:28) :
    Steven Goddard thinks it would take too long to have implemented such procedures.

    stevengoddard (21:12:38) :
    I said nothing of the sort. You are making things up.

    Oh really?

    stevengoddard (13:28:35) :
    Six days is not a very long time to come up with a set of procedures for dealing with a new paradigm.

    Regardless of what you think, your “Six days” is too long to implement simply daylight VMC restrictions. Six hours is a more realistic timeframe.

  203. wobble (16:44:08) :

    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

    Wobble, let me explain because I’m not arguing.
    When was the last time you heard about a car “accident” on the news? When did CNN last provide 24/7 coverage of a fatality car crash? (Other than Princess Diana…) The fact is that we can somehow conveniently avoid seeing ground travel fatalities because otherwise we might be terrified of driving. When two passenger cars collide and occupants die, it’s one at a time. One at a time is how we go anyway. It’s “acceptable”, and I use those quotes for a reason.
    When a plane, train, bus, ferry or other mass transport crashes, sinks, overturns, etc. and groups die, that is not acceptable. It’s all we hear about for days or weeks. We analyze it. We draft rules. We fix technical problems and establish procedures to deal with the human factor. In this regard, plane crashes are not “acceptable”.
    You can never actually quantify with certainty how many “extra” fatalities resulted on the ground from this incident, and I agree that it might well be an unacceptable number, but we’ll never know. Even if it was quantifiable I’m fairly certain that number would never be made public.
    I still maintain that the correct course of action would have been more thorough risk assessment, and I will always maintain that for this type of situation the people most able to perform proper risk assessment are those with something to lose: airlines, NOT government.
    By the way, the stereotype of the “cold heartless” corporation only concerned with their bottom line is absolute crap. Airlines depend on their reputation. Airlines have no interest in losing passengers, or their expensively trained people, or their incredibly expensive equipment. It is the airlines that had the absolute MOST incentive to perform accurate risk assessment. That was taken away from them, at the cost of much goodwill and an overall loss of customer satisfaction and confidence. Will the governments reimburse them?

  204. “Keith Minto (19:13:08) :
    Hey Skipper (18:44:27) :
    Thunderstorms are discrete, visible, radar detectable and dangerous.
    Airborne basaltic volcanic ash is diffuse,generally invisible, variable in density, not detectable on radar and dangerous.”
    Thunderstorms are not necessarily discrete. They can be in several hundred, even thousand mile long lines with severe convection from almost ground level to 45,000 feet or more. Convective cells actually build and fade in a few tens of minutes although the chain of storms can last for days. From a flight planning point of view there is little difference between severe convective weather and volcanic ash. Each hazard needs a certain level of avoidance that can be planned for.
    There is another similarity. There is ALWAYS convection going on; that is what you feel with the continual minor turbulence. There are even areas of clear air turbulence which can be and have been sufficient to bring down aircraft. In some areas of the world such as Florida there are always severe convective storms in the warmer months Similarly, there is ALWAYS volcanic ash in the air most of the time at extremely small concentrations.
    Someone needs to decide at what level of these hazards is it unsafe for an aircraft to operate in them.
    Therefore what is needed is sensible risk management and the identification of the person(s) who has the responsibility, accountability and authority over the decision and all its effects. Normally, the roles are extremely clear.
    * The meteo services supply information and in a format that is well defined. An occurrence that is hazardous for aircraft in flight is reported in a SIGMET (the hazard, its degree, the definition of the volume of airspace, and its motion in time and possibly how long).
    * The air traffic service provider is normally responsible for ensuring that the aircraft flight crew are fully aware of any active SIGMET that may affect the flight in the air traffic service provider’s airspace.
    * the aircraft operators and flight crew are responsible for obtaining all pertinent information NOTAMS, SIGMETS, weathers etc that may affect their flight and then planning the route of flight and the amount of contingency fuel and cargo/passenger weight. They are also the normal decision makers on whether to it is safe and commercially sensible to fly.
    * Airports may in severe weather conditions, enforce a ground stop and in poor visibility they impose maximum landing rates.
    What you will notice is that the decision making is at the operational level – not at national bureaucrat or political levels. The problem we saw with the Icelandic volcanic ash cloud was inept high level interference in what is a day to day planning and flight safety activity.

  205. Ian W (04:02:26) :
    There is nothing “day to day” about a volcano spreading ash all over northern Europe, and no one has presented one shred of evidence here that The Met Office did *anything* wrong.

    The eruption of the Icelandic volcano led to six days which were unprecedented in aviation history. As the cloud of ash from Eyjafjallajökull drifted across Northern Europe, British airspace was closed for the first time – and remained shut until Tuesday night. So what happened in between? And why did we support NATS in taking such drastic action?
    When the news about the volcano broke, we at the Civil Aviation Authority were faced with a huge challenge. The unequivocal guidance from manufacturers – based on such events as the multiple engine failure that affected a British Airways flight in 1982 – is that aircraft encountering volcanic ash must “AVOID AVOID AVOID”, and make sure there is absolutely no interaction between jet engines and ash.
     
    This advice works well in the US, with its vast open spaces, where you can fly around any ash or re-route to alternative airports. In the UK, with its congested, highly complex airspace, and a blanket of ash spread across the whole country, neither option was possible. There was no guidance that would have allowed the regulator to keep airspace open with any assurance of safety – and we were only able to reopen the skies after an enormous effort, in which we brought together nearly 100 organisations around the world.

  206. More on the ridiculous complaints lodged against the Met Office :
    From the original Telegraph article :
    http://www.telegraph.co.uk/news/7608722/Volcanic-ash-cloud-Met-Office-blamed-for-unnecessary-six-day-closure.html

    “We don’t even know what density the cloud should be in order to affect jet engines. We have a model that runs on mathematical projections.
    It is probability rather than actual things happening.”

    If they didn’t know what the safe level is, how could they possibly have kept British airspace open with an ash cloud covering the entire country?

    The Met Office has been blamed for triggering the “unnecessary” six-day closure of British airspace which has cost airlines, passengers and the economy more than £1.5 billion.

    The volcano “triggered” the closure of the airspace, not The Met Office. After the ash cloud dissipated at 30,000 feet, the airspace was reopened.

  207. The stranded passengers are getting screwed by British Airways.
    http://www.guardian.co.uk/business/2010/apr/23/stranded-britons-british-airways-seat-prices

    BA has increased the price of long-haul tickets from airports where customers remain stranded following the volcanic eruption in Iceland, placing them on sale to other travellers for as much as £4,700.
    Passengers stuck in India, China and the US said the earliest flights they have been offered leave more than two weeks from now even though the airline has put on sale tickets for flights that depart sooner. Many are furious the seats have been placed on the open market when they are desperate to get home and are facing increasingly chaotic situations.

    This is what BA said on Tuesday. No complaints about The Met Office then.

    BA cancels all short-haul flights
    LONDON — British Airways cancelled all its short-haul flights Tuesday after air traffic chiefs in Britain warned of a fresh cloud of volcanic ash from Iceland, the airline said in a statement.
    “Following the latest information… about the path of the volcanic ash affecting UK airspace, we regret we will not be able to operate any short-haul flights on Tuesday 20 April,” BA said.

  208. FLIGHT PLANNING
    Anthony, you miss certain aspects of flight planning when the risk is known – the flight shouldnt’ be dispatched without the fuel to divert if the ash location changes. To me that is normal practice, as for example in the case of an airport that has only one runway because the other is being worked on – you have to assume an airplane will crash and block that runway. Additional precautions can be taken, such as increased spacing between flights in case they have to divert.
    Symon makes the ridiculous claim that Canada does not have any airports – can s/he spell the well-known “Gander Newfoundland”? Can s/he spell “Greenland”, which Danish terriroty, which has an airport regularly used as a diversion, though its variable weather must be considered during flight planning.
    Observe that you show a route from the west coast of NA to the UK, whereas from east coast of NA to southern France would be different and much more in the NAT Track system than the flight you show. However, flights will normally shift substantially north or south from the great circle route depending on winds, which typically are westerly, to minimize fuel consumption. (IIRC against the wind would go north of the GC track, with the wind south of it. I was once on a 757 SEA-LHR non-stop and the tailwind was a very low 9 knots, we passed over Churchill airport in Manitoba.)
    Note that aircraft are supposed to have constant communication with ATC, and can relay through other aircraft they know are in the area and perhaps can see on their collision avoidance system. On oceanic routes they have HF and SATCOM, both voice and datalink, as well as VHF to contact other aircraft on designated frequencies especially the standard emergency one.
    I’ll also comment on flying above the ash – the crew must be able to descend if pressurization is lost, and will descend if an engine fails as they cannot maintain altitude (perhaps that latter diversion could be sideways if the area of ash is very narrow, the former descent must be immediate and rapid).
    And I’ll rant at the suggestion to take the risk of an airplane or two or going down. Nonsense! we in aviation don’t operate that way. We take measurably low risk, and operate to a high probability of success.
    Anthony, there is too much nonsense talk in this thread on top of your error. Rob Honeycutt, D. Patterson, Austin, acementhead, and Billy Liar, thank you for trying to get a bit of sense into it regarding flight planning.
    The big question in my mind is how airplane crews and ATC can know where the ash is real-time. See my ASH & AIRPLANES comment below.

  209. ASH & AIRPLANES
    The Seattle volcano example is not a great one, as Mt. St. Helens was known to be an eruption about to happen (areas around the bulging volcano had been evacuated). I tell you, having been involved then, that airplanes did fly through visible light ash from Mt. St. Helens, but at least one was damaged from heavier ash in Spokane WA (which had a substantial amount on the ground, engines could suck it up at low speed, whereas successful operations had only a small fraction of an inch depth).
    I am curious as to how ATC and the aircraft operators can know real-time where the ash is going and how thick it is, unless they only fly in daylight without water-based clouds. Traditionally weather radar did not show ash, though I expect radar developers have studied possibilities. Predictions must be conservative, or a safety margin added in defining no-fly areas. My impression is that the predictions weren’t great in this case though there was little data to go on, and the ability of airplanes to fly safely in light ash was not remembered.
    Note too that volcanic ash may vary, and is not necessarily the same as vegetation fire ash. (I suppose both depend on where the ash is, as further afield it would be finer as heavier particles would precipitate out sooner.)

  210. http://news.bbc.co.uk/2/hi/science/nature/8634276.stm

    over the past six days, the Natural Environment Research Council (Nerc) has run four test flights with its Dornier 228 research aircraft, to sample different layers of the plume.
    The UK’s Facility for Airborne Atmospheric Measurements also carried out a research flight on Tuesday. Each of these flights carried analytical instruments to detect particles of ash in the cloud, much of which is not visible to the naked eye.
    Commercial test flights, such as the one that was operated by British Airways, have simply checked for engine damage following the flight.
    It is the results of these test flights that have been translated into the updated regulations.
    The Met Office fed the new safe threshold figure into its “Name” model (Numerical Atmospheric-dispersion Modelling Environment) and mapped the density of the ash cloud.

  211. Keith Sketchley (08:08:32) :
    Anthony didn’t write this article, I did.
    The ability to divert to another airport depends on whether or not there are other airports in the region to divert to. If all of the airports in Northern Europe and the UK are shut down, there is likely to be a problem.
    This shutdown was a unique circumstance in many aspects and the CAA chose to take unique actions.

  212. stevengoddard (00:25:19) :
    I take it that you didn’t read the CAA explanation.

    Of course, I read it, Steven.
    Part of the reason it took 6 days is because they had to overcome the fact that they were handed bad data from the beginning. If the Met Office had been upfront about their cluelessness from the beginning, the process might have been expedited.

  213. stevengoddard (05:51:21) :
    no one has presented one shred of evidence here that The Met Office did *anything* wrong.

    Steven, if a weather service temporarily lost the ability to forecast weather for a certain region would it be ok for them to simply claim that the entire blacked-out region is full of thunderstorms, low ceilings, and zero visibility?
    Or should they merely tell the operators that they’ve lost the ability to predict the weather in that region?

  214. stevengoddard (09:17:03) :
    Keith Sketchley (08:08:32) :
    Anthony didn’t write this article, I did.
    The ability to divert to another airport depends on whether or not there are other airports in the region to divert to. If all of the airports in Northern Europe and the UK are shut down, there is likely to be a problem.
    This shutdown was a unique circumstance in many aspects and the CAA chose to take unique actions.”

    Steven it is my understanding that the _airports_ were open – but the _airspace_ was closed. Therefore an aircraft diverting would not have had a problem finding an airport. Indeed, it may even have been easier as there was almost no traffic.

  215. I knew this article would be controversial. Summarizing the arguments :
    “Computer models are useless” – remarkably out of touch viewpoint
    “West Coast flights don’t pass close to Iceland.” – wrong
    “GPS systems on planes aren’t accurate” – wrong
    “Decisions were made based on computer models without actual measurements” – wrong
    “The Met Office made the decisions” – wrong
    “Planes divert all the time” – Not hundreds of them with all major airports shut down for 2000km
    “I’m an expert, you know nothing” – Sounds like Hansen, Mann and Schmidt
    “You can sense ash clouds with radar” – wrong
    “Volcanic ash and smoke ash are similar” – wrong
    Perhaps the airports could have been open a day or two sooner, but that was not the Met Office’s decision.

  216. There was undoubtedly a need for caution. Interestingly though, Icelandair itself didn’t have a blanket grounding, although they did cut some services and most of their flights would have been through the thicker part of the cloud:
    “Despite closures of European airspace Icelandair has added new flights to its
    schedule when possible. Over the weekend Icelandair flew to Norway and Scotland and scheduled flights from Iceland to Finland and Sweden commenced this morning. Furthermore, several cargo flights have been operated between Iceland and Europe since the eruption started.
    According to the latest weather information Keflavik airport will remain open
    throughout the week. No disruption has been in Icelandair‘s scheduled flights
    to the USA and Icelandair will continue to operate flights from Europe to the
    USA over the course of the week.
    https://newsclient.omxgroup.com/cdsPublic/viewDisclosure.action?disclosureId=397020&messageId=477620

  217. stevengoddard (09:53:44) :
    Misrepresenting the statements and arguments is killing your credibility here.

  218. “stevengoddard (10:05:42) :
    Ian W (09:53:29) :
    The reason Heathrow (the world’s first or second busiest airport) was _closed_ was because there was concern that there was no safe approach through the ash.
    http://www.newser.com/story/86079/iceland-volcano-grounds-europe-flights-shuts-heathrow.html

    The airport may not have been allowing take-off’s and passengers would be told it was closed. But if an aircraft was _airborne_ and needed to land there, it would not have been turned away. There are in any case at least 20 airports and airfields in UK that could take a wide-body on diversion or in an emergency. In fact many of those would be more suitable for an emergency landing than Heathrow as they are not in urban areas.
    Oh and Heathrow is about 12th on the list for number of movements its claims that it is busiest ‘international’ airport is only valid if short flights to Europe count as ‘international’. However, it is probably at the maximum number of movements safely feasible on a 2 runway airport.

  219. stevengoddard (10:00:43) :
    Please produce some evidence supporting your claim that The Met Office is unable to forecast circulation in the atmosphere.

    Are you claiming that they were able to accurately predict or ascertain the location of the ash plume?

  220. stevengoddard (09:53:44) :
    Summarizing the arguments :
    “GPS systems on planes aren’t accurate” – wrong

    Are you trying to destroy your credibility?
    Produce any statements which indicate anyone on this thread claimed that GPS systems on planes aren’t accurate.
    It certainly wasn’t me. I’ve used GPS to drop mines into precise locations from aircraft.

    “The Met Office made the decisions” – wrong

    The Met Office most certainly made decisions regarding the type of information that they would disseminate – the wrong decisions.

    “I’m an expert, you know nothing” – Sounds like Hansen, Mann and Schmidt

    Nobody said that you know nothing. Some attempted to help your shortcoming with aviation. You arrogantly rejected their help.

  221. wobble (12:49:01) :
    I am still waiting to anyone to produce any evidence that The Met Office did anything wrong. Nothing but a completely irrational dislike of computer models and government.
    -f is how you search in a browser page. Perhaps you should try using it before commenting.


    D. Patterson (20:34:19) :
    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.

  222. D. Patterson (11:08:57) :
    And what exactly did I “misrepresent?”
    There has been no shortage of misrepresentation in this discussion – everything from the Met Office techniques, to their responsibilities, to the accuracy of their models.
    All modern weather forecasting depends on computer models, and the safety flying depends on both the models and the government bodies which make the decisions.

  223. Here is a video of the BA in-flight GPS system. It is very accurate. I have watched the plane circle in a holding pattern around London and it is always oriented in the correct position and direction.

  224. stevengoddard (14:40:30) :
    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.

    Sounds like a joke to me.

  225. Ian W (04:02:26)
    Similarly, there is ALWAYS volcanic ash in the air most of the time at extremely small concentrations. And I understand that in small quantities it can actually be beneficial and clean the turbine blades.
    That was interesting information on thunderstorms, but as for the decision to the favour public safety, that to me is a no-brainer.
    From a flight planning point of view there is little difference between severe convective weather and volcanic ash. I would say that the volcanic ash boundary is diffuse and uncertain, but if the problem of ash is encountered in-flight, where the aim is land safely, yes, but pre-flight, where thousands of lives are at risk, no.

  226. wobble (20:23:46) :(and all your other, sometimes reasonable, comments).
    =======
    It was fun, but, “a little knowledge can be dangerous”.
    I know from experience, how about you.

  227. Ian W:

    Thunderstorms are not necessarily discrete. They can be in several hundred, even thousand mile long lines …

    Excellent comment.
    stevengoddard:

    There is nothing “day to day” about a volcano spreading ash all over northern Europe, and no one has presented one shred of evidence here that The Met Office did *anything* wrong.

    How much ash fell on Heathrow, Paris, Brussels, etc? (Honest question, BTW)
    As it happens, just over a year ago, I got scrambled out of Anchorage due to the Mt. Redoubt eruption. Anchorage was closed for the better part of a week, and some north pacific air routes were closed.
    There is a difference here, though. When it was possible to fly, the airlines flew: unless the ash was in fact in the area and falling on the ground (my house got a dusting while I was gone), they made their own operational decisions about whether to launch.

    More on the ridiculous complaints lodged against the Met Office : “We don’t even know what density the cloud should be in order to affect jet engines …

    This hits the problem right on the head. It isn’t the Met Office’s business to know about how volcanic ash affects jet engines. It is the Met Office’s to give a density gradient map of the ash for the people who’s job it is to make operational decisions based upon meteorological information.
    The intelligent way to do this would have been to quickly re-open the airspace, and let airlines make operational decisions based upon how much they are willing to tolerate accelerated maintenance costs.
    Also, you really do need to re-do the post’s illustration. Very few airports have great circle routes passing over iceland. In the US, all airfields east and south of DTW do not get close.
    Keith Sketchley:
    Excellent comment.

    I am curious as to how ATC and the aircraft operators can know real-time where the ash is going and how thick it is, unless they only fly in daylight without water-based clouds.

    My point above. Absent an idiots notion of risk management, that is precisely what should have happened.

  228. precisely the A447 flight RIo-Paris had not loaded enough fuel to divert from its route when it should have avoided the turbulences. Nowaydays Airlines Companies economise on every possible bit, a heavy plane, fully fuel loaded, means more fuel expenses to keep the plane at its maximum speed

  229. Hey Skipper (18:13:55) :
    My passport is literally full of stamps from flights passing just south of Iceland, from San Francisco and Denver to London and back. The illustration is a fairly accurate representation of a typical route from the west coast.
    The CAA was not concerned with the operational costs of the carriers. That isn’t their job. They made their decisions about public safety based on the current guidelines in place at the time of the eruption. The UK is nothing like Alaska, it has very dense air traffic and the entire country was covered by the ash cloud. The Met Office provided accurate information using lasers, satellites, and computer models.
    If an airplane crashes on the UK, people die on the ground too. Like at Lockerbie.

  230. Hey Skipper (18:13:55) :
    “The intelligent way to do this would have been to quickly re-open the airspace, and let airlines make operational decisions based upon how much they are willing to tolerate accelerated maintenance costs.”
    ==========
    Just don’t say that in front of a jury, or your passengers.

  231. Here is my beef with Met Office/Computer model haters.
    I do computer modeling professionally, and have for the last 30 years or so on a wide range of geological and engineering problems. There are few things that don’t run off computer models directly or indirectly any more. They are an essential part of our infrastructure.
    I was also one of the first writers to point out the problems with Met Office seasonal and longer term climate forecasts. But there is nothing wrong with their weather models – they are current state of the art.
    So when people blindly attack the Met Office for things they do well, it muddies the waters for the real issues of concern. They have become a convenient, populist scapegoat for everything. If England doesn’t make it to the quarterfinals in South Africa in June, the press will somehow find a way to blame it on the Met Office.

  232. … precisely the A447 flight RIo-Paris had not loaded enough fuel to divert from its route when it should have avoided the turbulences.

    That is simply dead wrong.
    stevengoddard:

    The illustration is a fairly accurate representation of a typical route from the west coast.

    But it is completely failed to depict the variety of routes, or their location with respect to the actual cloud I didn’t say it wasn’t, only that the illustration is incomplete: you omitted the tracks that probably 80% of the flights to Europe use. On any given day out of SEA, there are probably a couple non-stops, a couple more to Amsterdam, and all the rest go via DFW, DTW, MSP, IAD, ATL, etc. In other words, you left out most of the picture.
    Note, I have not particularly faulted the Met Office (except for their apparent belief they should have a choice in operational matters), but rather the nonsensical decision to keep all the airspace closed for so long — that was simply nuts, and showed all the calm, cool,
    Most importantly, though, is what the models predicted, and what actually happened: How much volcanic ash actually fell on Heathrow and continental airfields? A lot? Some? None? What was predicted? How big were the errors?
    Compare how Redoubt, a volcano you can easily see from Anchorage, was handled, compared to this one, which must be a good 800 miles from Europe.

  233. Hey Skipper (18:13:55) :
    The intelligent way to do this would have been to quickly re-open the airspace, and let airlines make operational decisions based upon how much they are willing to tolerate accelerated maintenance costs.

    Odd, some days I feel invisible.

  234. “stevengoddard (18:44:35) :
    Hey Skipper (18:13:55) :
    My passport is literally full of stamps from flights passing just south of Iceland, from San Francisco and Denver to London and back. The illustration is a fairly accurate representation of a typical route from the west coast.
    The CAA was not concerned with the operational costs of the carriers. That isn’t their job. They made their decisions about public safety based on the current guidelines in place at the time of the eruption. The UK is nothing like Alaska, it has very dense air traffic and the entire country was covered by the ash cloud. The Met Office provided accurate information using lasers, satellites, and computer models.
    If an airplane crashes on the UK, people die on the ground too. Like at Lockerbie.”

    Steven I am sure your passport is full of stamps on your routine flights. A little information on how those flights work.
    Aircraft flying across the North Atlantic _normally_ follow the ocean track structure (colloquially known as the North Atlantic Track structure). There are 5 of these tracks in each direction the controllers at Prestwick centre in Scotland develop the tracks for the day UK time – mainly westbounds – and Gander Center in Canada for the night tracks -mainly eastbounds. The tracks are developed around the wind optimal modified great circle route between ocean entry and exit points typically a degree of longitude apart. Note that these are flexible tracks – if it is necessary to modify the exit or entry points or the routing due to weather then they will be modified. You will have sometimes entered the North Atlantic westbound flying over southern Ireland and other times over the Hebrides and Faroes this could be the same ocean track but modified due to strong upper winds. The same applies eastbound. Note that to a passenger things may seem very much the same, but these tracks are continually changed for efficiency – and to avoid weather and SIGMETs which include volcanic ash. Changing these ocean tracks is _routine_ every 12 hours by teams of controllers working with weather forecasters.
    At the same time considerable work is going on to allow aircraft to fly ‘User Preferred Routes’. A significant percentage of aircraft crossing the Atlantic already fly routes that are NOT on ocean tracks, this percentage is expected to increase and the SESAR (Europe) and NextGen (USA) air traffic system modernizations envisage ALL aircraft flying User Preferred Routes within the next 15 years.
    So where does that get us? The routes across the Atlantic are flexible, aircraft operators can to an increasing extent choose their own routes and in the mid-Atlantic this is normal (flights between the south-west of Europe and the northern South America, Carribean and southeastern USA. ) Most normal trans-oceanic aircraft types with a reduced freight load can fly for 10 hours or more. So aircraft can and do fly non-standard tracks to avoid weather and will always (note ALWAYS) have sufficient contingency fuel to avoid known and potential hazards.
    The problem occurs when there is intervention from agencies that are not normally involved in this decision making process, making decisions based upon poor information from models, which are using extremely poor data. It would now appear that the information was at least an order of magnitude WRONG. See this
    newspaper article
    This is what happens when senior managers get involved in routine lower level decision making that they do not understand. Air traffic controllers and aircraft operators and dispatchers routinely work _extremely_ closely with their weather staff. The role is the weather staff provide information plus Bayesian confidence level (“that’s what the Met Office model is saying- but I don’t have confidence in it – the ash will more likely be far more dispersed…”), Then it is up to the controllers to make decisions defining the routes and dispatchers which routes will be flown.
    Steven – confidence level in models is standard and not ‘an insult’ in all weather forecasting that’s _why_ they have a forecaster to interpret the model output – look at CCFP for example http://aviationweather.gov/products/ccfp/docs/pdd-ccfp.pdf There is always a confidence level. You will also note that the CCFP product is used to assist in flow control around severe convective weather – carrying fuel for and rerouting around forecast and potential hazards is a completely routine aviation activity.

  235. The safety issue is complex, but if the models used by the MET office were not able to locate the ash the funding should have been used for more land and sattelite based systems to see where the ash actually was.
    It is too simplistic an argument to say that planes can go down. We surely want mechanisms in place which give minimum intrusion to flight time with minimum risk. The question here comes down to whether the balance between funding measurement systems and models was appropriate, were the models overly cautious (rather than giving the best prediction they could and a margin for error) and can the models be appropriately created without the measuring systems to compare their results against reality? Without that the situation is unlikely to improve.
    The MET office does not deserve the benefit of the doubt with the previous global warming revelations. That is the price you pay for being caught manipulating the figures in engineering – everything you do in future has to be checked by somebody who doesn’t. Any fool can take funding to create a computer model which says nobody can ever fly if the risk to the model maker is only giving permission to fly when their is a risk of downing a plane.

  236. Ian W (04:26:07) :
    the information you gave is all accurate, but does not contradict what I am saying. I once was on a flight from London to San Francisco that traveled directly over Iceland and then northern Greenland, to avoid very strong west winds (100 knot) further south. All engineering problems have confidence levels. Given that the behaviour of the volcano itself is unpredictable, that placed limits on how accurate any ash forecast could be.
    larry (04:36:52) :
    The Met Office climate models are a different issue. The reason planes were grounded was because the CAA chose to ground them, based on the existing volcanic ash standards. It took several days for the aviation regulatory bodies to gather enough data and make the decision to change the standards. The argument that this was a failure of computer models seems to have no basis.

  237. The Daily Mash summarized the topic brilliantly, as usual:
    http://www.thedailymash.co.uk/index.php?option=com_content&task=view&id=2655&Itemid=76

    MET OFFICE FINALLY BLAMED
    20-04-10
    AFTER five days of disciplined self-control Britain finally gave in last night and blamed the Met Office for volcanoes.
    Across the country vaguely annoyed people found themselves rolling their eyes at the very mention of the Met Office before launching into a hellish 20 minute monologue about why it has always been rubbish when it comes to magma.
    Meanwhile a Facebook campaign has been launched demanding an inquiry into why it took so long to blame the national weather forecaster as Twitter users exchanged ideas on the best way to kill and cook Philip Avery.
    Roy Hobbs, a television viewer from Peterborough, said: “If something is happening in the space above my head then surely that’s the responsibility of the Met Office. And if not then I honestly don’t know what the Met Office is for. I really don’t.”
    ……

  238. u.k.(us) (16:53:17) :
    It was fun, but, “a little knowledge can be dangerous”.

    Are you criticizing Steven Goddard for refusing take the advice of experienced aviators and tweak his argument to make it more reasonable?

  239. The reason planes were grounded was because the CAA chose to ground them, based on the existing volcanic ash standards.

    Steven, are you claiming that the CAA grounded planes without any input from the Met Office?

  240. codetech:
    You shouldn’t be invisible, you were exactly right all along.
    Ian W:
    Thanks for a very clear and concise description of how the NAT system works. It is worth noting how dynamic that system is: at least three times out of five, the actual route clearance (received about an hour prior to track entry) was not the one in the flight plan.
    stevengoddard:
    How worthwhile is a forecast that is off by — at least — an order of magnitude?
    Particularly considering how the CAA reacted to the volcano with the same calm, cool, analytical approach one expects from a pre-teen girl confronted with a spider.
    From the newspaper article cited immediately above:

    Moreover, while the Met Office maps were saying that many thousands of square miles of airspace posed a risk, other forecasts – such as those from the US firm WSI, used by BA and 24 other airlines over the Atlantic and the Americas – suggested the potentially dangerous area was much smaller.
    The reason, said WSI’s aviation manager Roy Strasser, is that WSI ash forecasts show only air where ash is likely to be visible. ‘Experience shows it’s only when ash is visible that it’s concentrated enough to be a hazard to aviation,’ he said.

  241. wobble (08:39:24) :
    If you have a specific objection to something, then please articulate it. The “I am an aviator and you are not” statement doesn’t carry much weight.
    You keep saying that the decisions were made by the Met Office based on models, which is incorrect at many levels.
    And yes, west coast flights to Europe do normally pass close to Iceland. You don’t need to be a pilot to figure that out, any more than you need to be a climate scientist to know that it is cold and snowy outside.

  242. Hey Skipper (08:55:29) :
    The aviation authorities make their decisions based on current conditions, regulations and standards.
    The fact that some people don’t like those conditions, regulations and standards doesn’t really make a lot of difference, does it?

  243. stevengoddard (09:05:28) :
    If you have a specific objection to something, then please articulate it.

    Well, I’ll start with your implication that flights originating in the US wouldn’t have the range to divert to the west if they ran into ash conditions they believed were dangerous.
    Next is your implication that flights couldn’t have been limited to daytime VMC.
    Also, the fact that you didn’t answer my most recent question. I’ll repeat it.

    Steven, are you claiming that the CAA grounded planes without any input from the Met Office?</blockquote.
    Lastly, I want to know how many extra deaths were caused by the increased highway traffic because:
    Decreased air travel = Increased highway travel = Increased deaths

  244. wobble (10:37:32) :
    It is not the job of the CAA to control automobile traffic.
    You are missing the point about diversion. One plane can divert and do frequently. The problem is allowing hundreds of airliners in the air which may all have to divert.
    It is 7,000 km from Denver to London. The flight is a 767 which has maximum range of a little over 9,000 km on fully loaded fuel tanks. That is not enough range to get back, particularly fighting the wind flying west.

  245. 5th INTERNATIONAL WORKSHOP ON VOLCANIC ASH Santiago, Chile 22-26 March 2010.
    Convened by the World Meteorological Organization
    In collaboration with the International Civil Aviation Organization
    http://www2.icao.int/en/anb/met-aim/met/iavwopsg/Lists/Workshops/DispForm.aspx?ID=3
    P.10: Quote:
    ‘…Referring to the need to have established alert thresholds, Airbus was then asked what is the safe particle size and concentration of ash that is sustainable by aircraft. Similarly, the same question relating to Sulphurous gas was also asked. Airbus could not provide an answer to either question because this information is not readily available. Airbus highlighted that flight in volcanic ash laden atmosphere is not part of the environmental specifications to which aircraft and engines are built.
    However, an action item was taken by Airbus to write to the engine manufacturers asking if an answer is available. Airbus will respond to IATA…’
    If aircraft manufacturer doesn’t know – then who may do so?
    BTW.
    http://www.boeing.com/commercial/aeromagazine/aero_09/index.html
    See Volcanic Ash Avoidance..
    ‘…Boeing has always advocated that flight crews avoid volcanic ash clouds or exit them immediately if an encounter occurs…’
    Perhaps someone needed to keep the airlines in check?
    – Pip

  246. stevengoddard:
    As an aviator, I have some serious objections to just about everything you have said on this thread.

    It is 7,000 km from Denver to London. The flight is a 767 which has maximum range of a little over 9,000 km on fully loaded fuel tanks.

    I don’t know which 767 variant you are on, but I would bet it is an ER version, which has a range from 10,400 to 12,200 km.

    That is not enough range to get back, particularly fighting the wind flying west.

    You simply do not understand the diversion problem
    No, of course it doesn’t have enough fuel to fly to LHR, fly an approach and missed approach and return all the way back across the Atlantic, but that cannot possibly be the situation.
    The ash cloud’s density must be inversely proportional to its diffusion.
    If the cloud is dense, it must be localized. The resulting problem is nothing more than a typical problem which ATC and pilots must be prepared for everyday; contrary to your assertion, sometimes lots of airplanes have to divert. (For example, see the video someone above linked showing how that works when a localized meteorological phenomena closes an airfield.)
    All those airplanes, just as with your DIA – LHR flight, had enough fuel to fly hundreds of miles beyond their destination, and still arrive with required fuel reserves. In Europe, that puts the number of available airfields somewhere in the high scads.
    To be further contradictory, the arrival rate at LHR is (guessing here) about sixty per hour. So the diversion problem at LHR can never amount to hundreds of airliners, because to reach that number requires including aircraft en-route or that haven’t even taken off. The en route aircraft have much more fuel, and, therefore, options, because they haven’t used the portion of fuel required to get to the descent point, plus descent, approach, missed approach and climbout, and fuel burn to the alternate.
    Obviously, the aircraft still on the ground simply don’t count, so don’t count them.
    On the other hand, if the ash cloud is widespread, it cannot be dense enough to present an air safety issue, particularly at the low thrust settings used during descent.
    So, either the ash cloud is in principle no different a problem than, say a runway closure due to snow, or it is no problem at all.

    The aviation authorities make their decisions based on current conditions, regulations and standards.

    True as far as that goes. However, the aviation authorities did not, in fact, make their decisions based upon current conditions, but rather forecasts that were, to put it as kindly as possible, spectacularly wrong.
    In so doing, they deprived themselves of invaluable meteorological data. Ash goes where the wind takes it. So, if you want to know where the ash is going, you have to have a good idea of the winds aloft.
    As it happens, our flight plans generally have very good wind predictions, because the forecast models are continually modified by real-time data.
    The airplane I fly continually calculates the wind. Because the GPS velocity error is essentially zero, that means the wind calculation is accurate to within a degree and a knot. Most transoceanic airplanes have CPDLC (controller to pilot data link communication). My airplane frequently uses satcom to automatically transmit all kinds of information, including wind velocity.
    That means that our weather department has a very good idea of winds at cruise altitudes, which, depending on traffic and weight, which typically ranges from 29,000 to 36,000.
    So, shutting off all the airspace, based upon a hysterical reaction, helped ensure that a forecast that was pretty lame to begin with got essentially no real time data with which help put things less wrong.
    —-

    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

    At the volcano they do, but until there is light-speed volcanic ash, not everywhere.
    Here is how it would have gone, without pig-ignorant bureaucrats abetted by indefensible Met Office forecasts:
    Volcano pops off. Two-hundred mile surface to infinity no-fly zone established around volcano. En route aircraft re-route if able, or divert. For all aircraft that have not yet passed Iceland eastbound, any number of Canadian and even US airfields are well within range.
    NB: the number of aircraft in question amounts to those going between Europe and SEA, and maybe SFO, LAX and DIA. Number of aircraft en route? Don’t know for sure, but 10 from those airports isn’t a bad guess.
    Airline dispatchers fuel subsequent aircraft to take account of the airspace restriction, plus the possible movement of the cloud based on current winds during the time from takeoff to landing.
    Controllers get pilot reports, which, in combination with updated wind profiles, are used to plot actual ash location and movement. (Initial uncertainty might restrict operations in the area to day VMC.)
    That, in turn, might increase required fuel reserves. If so, that might cancel some flights, or require payload penalties, or change in equipment.
    Continue to update ash cloud location based upon PIREPS and winds, remembering that ash sufficiently diffuse to be invisible presents absolutely no hazard to flight.
    That is how it worked when Redoubt popped. An eruption closed airspace that included Anchorage. Wait for a bit to see where the ash goes, then re-open ANC if there was no visible ash-fall headed towards the airport. Airlines would then launch, or not, based upon their own operational decisions.
    And that volcano was only 90 miles away, not 800-ish.
    BTW, how bad does a forecast have to be before it is no longer defensible?

  247. wobble (08:39:24) :
    u.k.(us) (16:53:17) :
    It was fun, but, “a little knowledge can be dangerous”.
    Are you criticizing Steven Goddard for refusing take the advice of experienced aviators and tweak his argument to make it more reasonable?
    ===========
    First, as you know, i wasn’t criticizing Steven.
    Second, whats with the fixation about increased highway deaths? Do you propose all travel is done by air, to save lives? What about trains?
    The “advice of experienced aviators”, doesn’t mean much when the populace has ceded decision making to Government Bureaucrats.

  248. Hey Skipper (14:21:13) :
    767 range is listed on wikipedia from 9,400 to 12,200 km. LAX-LHR is 9,000 km.
    LHR isn’t the only airport in Europe. Suppose the average long haul flight is 8 hours. One third of the long haul arrivals are in the air at any time. There are probably hundreds of long haul flights on their way to Europe every night.

  249. Hey Skipper (14:21:13) :
    …….”That is how it worked when Redoubt popped. An eruption closed airspace that included Anchorage. Wait for a bit to see where the ash goes, then re-open ANC if there was no visible ash-fall headed towards the airport. Airlines would then launch, or not, based upon their own operational decisions.”
    And that volcano was only 90 miles away, not 800-ish.
    ===================
    Apples and oranges.
    The airspace over Europe has 100 if not 1000 times more traffic than Anchorage.

  250. Steven,
    You do realize that all London area airports can close at any time, right? You realize that all inbound aircraft would need to be diverted, right?

  251. stevengoddard (11:05:59) :
    It is not the job of the CAA to control automobile traffic.

    It’s sad that you make sophomoric comments instead of answering a difficult question.
    Now, are you claiming that the CAA grounded planes without any input from the Met Office?
    If not, then what input did CAA receive from the Met Office?

  252. stevengoddard:
    I don’t know how that number is calculated. If it is flame-out on touchdown — which makes it a useless number — then the 9400 km variant isn’t on the LAX – LHR route.
    If it is a useful number, then 9400 km range means that is the farthest it can fly and have an operationally useful fuel reserve remaining.
    Either way, it doesn’t matter. No airplane is dispatching from anywhere without the ability to make a detour en route. An unpredicted squall line of thunderstorms can arise just as quickly as a volcano, and across a much greater area.

    LHR isn’t the only airport in Europe. Suppose the average long haul flight is 8 hours …

    As you said above, that volcano can erupt in a blink of an eye. May I presume you are never flying to Europe again?
    Like I said above, area and density are inversely related.
    There is simply no way an ash cloud from a volcano 800 miles away can, without substantial warning, shut down all the airports in Europe at once.
    If winds aloft are strong enough to move the cloud quickly, then it isn’t dispersed, therefore any closures would be localized.
    On the other hand, if the winds aren’t strong — as in this case — then the cloud can’t move very fast, which means there is far more time for ash to fall out of the sky, which means airports won’t get closed.
    So, yes there are hundreds of long haul flights on their way to Europe every day.
    On average, though, half of them are less than halfway there.
    Adding to the stupidity of this is history. Eyjafjallajökull had no more than a third the ejecta of Mt St Helens, and it was less explosive.
    When was the last time a volcano of that size caused anything like a significant ash fall 800 miles away?
    I’ll bet “never” is the right answer. Mt St Helens ash fall was zero further than 450 miles from the mountain.
    So to bureaucratic pusillanimity* and a Met Office forecast that would finish second to throwing darts blind, we can add bottomless ignorance of history.
    Every one of those stranded passengers, everyone who had important travel plans, should be focusing red hot hate beams at the EU, CAA, and the Met Office.
    Without whose contribution, none of that public “service” would have been possible.
    ——-
    * one word that says it all: timid, timorous, cowardly, fearful, faint-hearted, lily-livered, spineless, craven, shrinking, chicken, gutless, wimpy, wimpish, sissy, yellow, yellow-bellied.

  253. u.k.(us) (15:17:30) :
    whats with the fixation about increased highway deaths? Do you propose all travel is done by air, to save lives? What about trains?

    Canceling flights causes increased highway travel which causes increased deaths. This fact is independent of the dynamic that occurs with train travel. This concept really isn’t that difficult.

    The “advice of experienced aviators”, doesn’t mean much when the populace has ceded decision making to Government Bureaucrats.

    Yeah.

  254. The question comes down to whether the met office’s predictions caused the uk authorities to stop air flights – and where the models appropriate for making that judgement. According to the telegraph the maps produced by the met office were very different to the ones produced by the sensors on the ground – hence the UK had 100% shutdown whereas most of Europe had partial shutdown. This piece appears to suggest that it is wrong to question the models because lives are at stake. As an engineer I cannot accept that. The job of the computer models are to inform the decision makers. If the models are wrong they serve no purpose and ground measurements need to be increased until the models agree with the ground measurements and add extra detail.
    By defending the models you are in effect cutting the crucial feedback step which would make the models fit for purpose. The model makers have to be taken to task for making incorrect predictions. They then must update the models where possible. At the moment they appear to be allowed to check their own homework. That has to stop if they are to be used for public policy.
    Computer models we rely on are built up over decades with every error sent back to the developpers, quality assurance mechanisms set in place – and most of them are deterministic. A computer model of a new device would fail if any state in the system was incorrect after running a lot of code, the models would be fixed. Computer models are only as good as their quality assurance. The met office has to demonstrate that their quality assurance was up to the job. Talking about issues of planes falling out of the sky is a separate question.

  255. stevengoddard (19:16:52) :
    I’ll post it again for you – for about the fifth time:

    By all means, post it as many times as you’d like.
    But answer the question.
    Are you claiming that the CAA grounded planes without any input from the Met Office?

  256. Anthony, I apologize for assuming you wrote the article defending the UK’s Met office from a position of ignorance of aircraft operations.
    stevengoddard, thankyou for pointing out my error.
    FLIGHT PLANNING MORE
    Steven, please read my point that flight planning takes into account availability of diversion airports. (I mentioned a flight diverted to Greenland, but that was due to a bomb scare (specifically, it landed at Soendre Stroemfjord which is a historic diversion/refuelling airport but somewhat sensitive to weather so cannot be planned on if forecast is not good).) Note that there is an airport in the Azores, available for at least emergencies such as the A330 whose flight crew did not catch that they had a fuel leak early enough to turn back. (Yes the Azores are well south but flights from the east coast of NA. See http://gc.kls2.com/cgi-bin/gc?PATH=kmco-lfpg&RANGE=&PATH-COLOR=red&PATH-UNITS=mi&PATH-MINIMUM=&SPEED-GROUND=&SPEED-UNITS=kts&RANGE-STYLE=best&RANGE-COLOR=navy&MAP-STYLE= or
    http://www.gcmap.com/mapui?PATH=kmco-lpaz&RANGE=&PATH-COLOR=red&PATH-UNITS=mi&PATH-MINIMUM=&SPEED-GROUND=&SPEED-UNITS=kts&RANGE-STYLE=best&RANGE-COLOR=navy&MAP-STYLE=
    and zoom out to see where the Azores are. (Those routes are Orlando Fl to Santa Maria in the Azores to Paris deGaulle which is in northern Europe), chosen to show where the Azores are whereas normally flights would be non-stop, and choosing Florida to show an east coast departure point as I and “Hey Skipper” point out. Anyone can look up the non-stop route and try airports further to the east and south of , which flights from the eastern US commonly go to (into Germany for example, from the east coast and places like Atlanta) – note where the greatest population is in the US thus the greatest demand for flights to Europe.
    SOP on oceanic/remote flights is to monitor fuel against flight plan as the flight progresses – especially easy to do as the flight plan includes way points with fuel expected to remain at each of them.
    stevengoddard, the reason the article is useless (your term) is that your premise is false – that airline flights always do not have enough fuel to divert. It has been pointed out that flight planning is supposed to take into account conditions – over the pole they even have to watch fuel temperature which can go below accepted limit on long flights when temperatures are quite low. So whether or not airspace was closed the flight would have to be planned for current risk – that is SOP and regulation. Yes, there is risk that an airline will not do the right thing – which was the case of the A330 that diverted to the Azores, and the case of a South Pacific airline that was veering into the USSR, and some cases of poor oceanic flight planning that came close to running out of fuel. That’s the nature of choosing your service provider, expecting competence. (E.G: Think about what is different for this flight if anything. (If going into a new area, study more and ask for advice – going deep into middle Africa, for example, don’t depend on navaids being on the air as scheduled – carry ample fuel to go to another country. Electromagnetic storms might affect communications. Etc.) Triple check and make conscious decisions (at top of descent, or “oceanic gateway”, or point-of-no-return if the flight has one, for example.

  257. MISCELLANEOUS
    Meanwhile, other comments that need review are:
    – stevegoddard, reread this thread to see what people are saying about routings that will take you over Iceland, I don’t read anyone halfways credible saying that flights would never go over Iceland, but credible people are saying that is not the only possible way to get to Europe especially from the east coast of the US (which BTW you can fly to from the west coast). The whole question of whether or not flights go directly over Iceland is irrelevant – obviously some do, but the ash isn’t just over Iceland.
    – I demand proof of the claim that AF447 did not have enough fuel to divert. Note the length of its non-stop flight, much of the latter part of it near land – when it crashed it had should have had enough fuel to divert. Many flights threaded through typical tropical storms in the same area that night, perhaps taking risk no one should not have, it is likely the AF447 crew got caught in one of those tall moist ones typical of that area and the airplane and crew did not cope well with it.
    – people, the cabin display is not used by the pilots, as has been pointed out – thus does not have the safety rigor of flight deck systems, but is probably supplied with position data from those systems thus should be accurate as long as it is correctly displaying the data. Which BTW is not necessarily from GPS though that is increasingly common (the traditional system being Inertial measurement), sometimes blended so each sensor source helps the other and errors are more likely to be caught.

  258. Dr. Roy Spencer will be interviewed tonight (Mon.) on Coast-to-Coast from 10pm to 2am Pacific time.

  259. Keith Sketchley (11:40:09) :
    Try diverting dozens or hundreds of long haul flights at the same time. with most airports in Europe shut down.
    Let me know how that works out for you.

  260. “stevengoddard (05:01:20) :
    Keith Sketchley (11:40:09) :
    Try diverting dozens or hundreds of long haul flights at the same time. with most airports in Europe shut down.
    Let me know how that works out for you.”

    Steven, you are obscuring your main point by making incorrect exagerated statements in areas where you have less expertise.
    The airports were shut for departures . I realize from a passenger’s perspective this means that they are shut down. However, the airport itself and its staff would still be there and available for arrivals especially those in emergency. Moreover, it is not uncommon in an emergency (and I have done this myself) to contact the managers of an airport and have it (re)opened outside its normal hours.
    There are NOT hundreds of flights to divert; there would only be those beyond their normal point of return that would continue that would probably be well less than a hundred. And all those airports open (although without departures) and other traffic would have had NO problems in accommodating the flights. There are also military and industry airfields which were open and perfectly capable of accepting wide-body aircraft.

  261. Ian W (05:42:38) :
    Most of the airports in Northern Europe including most in the UK and France were shut down last week because it was deemed that it was not safe (under existing standards) to fly through the ash cloud.
    The fact that you think they would have allowed people to land doesn’t do any good if there is considered to be no safe approach to the airport.
    The point isn’t whether or not some of the planes might have been able to find a place to land safely. The point is that under existing regulations, the CAA had no choice but to shut down the airspace.

  262. WHO ACTUALLY CLOSED UK AIRSPACE?
    – I urge separation of the issue of forecasting location and amount of ash, and measuring it, from determination of acceptable threshold for airplane operation.
    – The Met Office routinely provides forecast for water and in the air and how it moves (to spell it out, that’s clouds, precipitation, and storms. The Met Office runs the UK’s ash advisory service.
    – But I expect the operational safety authority, the CAA, to set the threshold used to make the decision to close airspace. (Richard Briscoe is in effect saying that.) They are the authority on technical operation of airplanes.
    – A Telegraph article of April 21 indicates it was the airspace control organization NATS, which has delegated authority from the CAA, who chose the initial threshold.
    – (NATS also controls the eastern mid-north Atlantic oceanic area, delegated from a group of countries probably via ICAO. That might be relevant to flights from the US east coast, whereas the true-north Atlantic that flights from the west coast of NA go through is controlled by centres in Iceland and Greenland, under the same delegation. The Western mid-north Atlantic oceanic area is controlled by Nav Canada. Lower altitudes, such as below 19500 feet, and areas near coastlines including islands north of Iceland, may be handled by local control centres. To my limited knowledge they cooperate well.)
    – Talk of “models” is confusing. Measurement feedback should be included, as it eventually was to some degree according to the Guardian’s article on deciding to relax the threshold. The output routine of the model could include threshold simply to generate useful plots for decision makers – apparently it did. However the threshold should have come from the airspace control authority.
    – People say the Met Office’s initial forecast of location of ash was pessimistic, but that is variable with winds and how quickly it falls – at one point it was showing up off the east coast of NA, though it may not be difficult to find some ash in the air so that is another reason why having a realistic threshold is so important.
    – The Guardian article on deciding to relax the threshold says the CAA made the relaxation decision and UK transport secretary Lord Adonis depended on them.
    – Note too that the CAA of the state of registry of the airplane has some authority over operation of it, though I don’t understand how state of registry and area of operation differences are decided in a technical case like ash (rather than rules to keep airplanes apart which must be followed by everyone in the airspace) and the UK case is further compounded by the pan-European airworthiness regulatory authority for the technical capability of airplanes.

  263. Try diverting dozens or hundreds of long haul flights at the same time. with most airports in Europe shut down.

    That is unreasonable.
    Ash cannot move both far and wide enough to shut down most, or even a few, airports in Europe within the en route time of even long haul flights. There have been many volcanic eruptions in recent history, has even one of them created such an outcome?
    That ash fall forecasts proved so laughably wrong is one thing.
    The imposed policy is something else altogether. By mandating what amounts to a zero-tolerance policy for ash, then there is no way of saying how far from the volcano was far enough.
    There was never a time when there wasn’t a safe approach to virtually all of the airports in Europe during the entire shutdown.
    At all times, flight through whatever ash was present would have produced no safety impact whatsoever.
    It might have increased maintenance costs for the airlines down the road, but that is another matter altogether.

  264. Hey Skipper,
    Volcanoes in Central America and Indonesia don’t cause a lot of disruption because there aren’t a lot of planes landing nearby. When an explosive volcano goes off in Europe, it is a completely different story.
    If Long Valley blows, it will spread deposits of ash across most of the US.

  265. stevengoddard says:
    Try diverting dozens or hundreds of long haul flights at the same time.

    The possibility of having to divert dozens or hundreds of long haul flights exists every single day!

    with most airports in Europe shut down.

    Did these airports need to be shut down?

  266. stevengoddard:

    Volcanoes in Central America and Indonesia don’t cause a lot of disruption because there aren’t a lot of planes landing nearby. When an explosive volcano goes off in Europe, it is a completely different story.

    There are two problems here.
    First: The blanket closure of essentially all airports in Europe north of the Alps and east of the Pyrenees meant nothing was going anywhere, period. The decision to do so, based upon both world class bureaucratic timidity, aided by an ash fall model that was comprehensively wrong, applied just as much to even one airplane as all of them.
    This had nothing to do with operational decisions of any sort: even airplanes that had enough fuel to turn around and go home weren’t allowed to fly.
    Second: This volcano did not go off in Europe. It went off in Iceland, which is (referring to my North Atlantic plotting chart), roughly 500 miles from Inverness, Scotland, and nearly 900 miles from London.
    Flights from Detroit and east would remain at least 400 miles from the volcano on their normal routes.
    Mt St Helens was at least three times as big an eruption as E+15. Had sane people, using normal risk management simply decided to draw a six hundred mile circle around the volcano, which, so far as I have been able to determine, encompassed even trace amounts from MSH, then this would have been a non-event.
    Did any measurable amount of ash fall on the ground even as far as 600 miles away?
    Never mind 1000+.

  267. stevengoddard says:
    April 27, 2010 at 2:18 pm
    Hey Skipper,
    Volcanoes in Central America and Indonesia don’t cause a lot of disruption because there aren’t a lot of planes landing nearby. When an explosive volcano goes off in Europe, it is a completely different story.

    More gross misrepresentations from you. The volcanic eruptions in the Asia-Pacific region were astride some of the busiest trans-oceanic air routes in the world. The only factor which made the recent Icelandic volcanic erupton “a completely different story” is the utterly irresponsible response of unnecessarily shutting down European airspace.

  268. Ian W
    thanks.
    I see two different diversion scenarios with two different fuel reserve requirements.
    One is where there is little risk of something like a volcano interfering with air travel. A flight might then have a PNR but ample reserves, as I believe used to be done for Hawaii where bad weather would soon move on.
    But in the case of known risk, such as an imminent eruption or an active eruption but the usual variability of winds (as apparently the case this year from Iceland), shouldn’t a flight plan include reserves to divert well out of the area?
    A parallel might be how flight planning was done into the High Arctic and to oil platforms off the east coast of Canada, last I was close to those operations. In winter flights had to carry fuel to reach the destination and an alternate in the general area, make an instrument approach at each, then move on to a known dependable landing point if unable to land up/out there. Typically in those cases that meant return to point of departure, though there was the economic consideration for customers that they didn’t want to be in a third place they had no connection to. A lot of fuel, which cut into payload, but that was necessary because the weather was not dependable.

  269. ASH CONCENTRATION THRESHOLD
    – In the 1.7 Billion thread Richard North discusses ash measurement, as does the http://www.http://www.guardian.co.uk/ article “Iceland volcano ash cloud: The full story of how the airlines won the battle for the skies” including , and the ICAO document detailed in a later post herein.
    – Observe that when the UK CAA made its decision to relax, airliners were already flying over the UK – it sounds as though the conservatism was only in UK lower-level airspace. A Reuters report indicates continental operations may have restarted on April 21, whereas the Guardian article indicates UK airspace was opened late that evening.
    – Does anyone have references to what the no-fly threshold originally was? The article linked above says “ten billionths of a billion of a gram…per cubic metre” which is not correctly stated (a superfluous “billion” word). If ten billionths that is several orders of magnitude lower than what was eventually accepted (2000 micrograms per cubic metre with precautions), even if one calculates on the smaller US billion (10E09 not 10E12 (have to check Canada, it tends to be bilingual :-). “Micro” is 1E-06? (Can anyone measure ten billionths of a gram per cubic metre, real time?)
    – Another article http://www.dailymail.co.uk/news/article-1268615/The-ash-cloud-How-volcanic-plume-UK-twentieth-safe-flying-limit-blunders-led-lock-down.html# gives a value for real ash concentrations over the UK as one-twentieth of the relaxed limit of 2000 micrograms but is not specific as to area and date/time.
    – The Daily Mail article claims that the ICAO guidance is zero tolerance, but that the US and other countries ignore that, however another part of its articles muddies that. It also claims that some weather services such as WSI used different criteria than the Met Office, quoting WSI as using a “visible ash” threshold (which Mt. St. Helens experience suggests to me is itself conservative).
    – The article referring to redeployment of lasers doesn’t specify how the lasers were used – perhaps pointed up and detected by satellites, which gives visibility that might be correlated to density if the ash is uniform in light blocking effect (similar to RVR measurement for horizontal visibility at airports). Sounds coarse and approximate.
    – The article also says the UK was in the unfortunate position of having its high-flying measurement aircraft down for maintenance so had only the DO228 which cannot fly high. (It’s data should be quite useful to correlate to laser measurements.) I ask why someone else couldn’t help out. (Airlines in continental Europe made less sophisticated measurements I suppose.)
    – The stuff moves around (no kidding, Keith!), that’s why measurement and forecasting is essential. Initial forecasts in this case were of wind toward the UK, but those shifted to a more northeasterly direction. (In the eruption that the NASA DC-8 was affected by the winds were to the NNE.) In this case ash showed up off the east coast of Canada, though note it can circle the globe. Note that the main airport in Iceland was not as badly affected in this case as you might expect, perhaps because volcanoes often push ash very high (45000 feet from the Mt. Hekla eruption in Iceland in 2000) and it is then carried elsewhere by wind as it begins to fall. (See map and satellite image of the ash cloud the NASA DC8 encountere.)

  270. GUIDANCE & OPERATIONAL ADVISORIES
    – ICAO has a 2007 vintage document about volcanic ash and other air contaminants downloadable n/c at http://www.icao.int/icao/en/9691.pdf. It discusses the nature of volcanoes and their ash (which varies – data from Mt. St. Helens is included), measurement of ash concentration, effect on jet aircraft (which may vary with engine vintage, risks also include possible blockage of pitot tubes and contamination of electronics), a list of incidents with brief mention of severity, and even a very long list of eruptions that produced ash of concern to aviation. It provides guidance on handling an inadvertent encounter. There seems to be confusion in the media over the word “avoid”, but paragraph 3.4.8 does say AVOID AVOID AVOID because it claims there are no agreed values of acceptable concentration. (That seems to have left some people in the modern “zero is acceptable” unrealistic box.) That is unfortunate given Mt. St. Helens experience. Yet in section 5.1.3.1 it talks of continuing operations at an airport, especially to get people out (which I see as risky with much ash on the ground) but also landing – and provides guidance to minimize damage and risk. Obviously a lot of effort went into the document, and it is quite educational for operators, maintainers, airports, forecasters, and ATC, but it seems contradictory (as if a committee effort) and wimps out on practical guidance.
    – The European authority EASA issued an advisory and bulletin with guidance for operating in air with a low concentration of ash. It includes routine inspections daily, and after each flight if certain phenomeon are observed.
    – They advise that ICAO will work on standards for ash concentration – about time given the frequency of volcanic ash plumes. (The draft report of the WMO International Workshop in March 2010 says Airbus will contact engine manufacturers, and besides quite technical discussion talks about better information in various aspects as well as more coordination and use of existing resources. Boeing, GE, Rolls and Pratt & Whitney are not in the draft participants list but Pratt is shown as a panel member in one session as is Lufthansa. Qantas (who presented on costs of operating in a volcano environment) and the Airbus rep for LAN Chile airline arek listed as is a Chilean regulatory official.) A Boeing article says Alaska airlines is set up to get lots of information on ash in the air to make decisions and advise pilots (having of course experienced Mt. Redoubt and Mt. St. Helens erupting in their areas of operations). I read that USGS heads a volcano observatory for Alaska, which is on many long-range air routes, and that organization coordinates with Russian experts. It seems there is much information extant, though not as precise as is desired, but it must be disseminated and digested.
    – Note that the NASA DC-8’s engine damage was from an Icelandic volcano. The technical report shows the airplane lifing off with substantial powder on the ground – I presume it was snow! – but the airplane definitely had an airborne encounter in darkness well north of Iceland enroute to its testing base in Sweden and lesser encounters during testing. The flight path was 800 nautical miles from the volcano, 200 nm beyond forecast area though the ash was moving NNE. (The ash was not as severe as the 747 inadvertent cases, with no static discharge indications for example, but was measured by onboard instruments. The report shows “aerosol number density, cm-3”, from a “condensation nuclei counter”.)
    – This is of course serious work. The typical jet engine operates on a safe life concept, anything that severely reduces part life but is undetected could have serious consequences beyond simply loss of thrust from one engine. However it seems that many people thought only of complete avoidance – which is wise if the nature of the ash in the air is not known – overlooking that it will disperse widely but much of that coverage will be light concentration.

  271. Iceland[note 1] ( /ˈaɪslənd/ (help·info)) (Icelandic: Ísland (names of Iceland); IPA: [ˈislant]) is a European island country located in the North Atlantic Ocean[6]
    In the ensuing centuries, Iceland became one of the poorest countries in Europe.
    The economy was greatly diversified and liberalised when Iceland joined the European Economic Area in 1994.
    Iceland is a part of Europe, not of North America,
    Iceland is the world’s 18th largest island, and Europe’s second largest island
    The volcanic eruption of Laki in 1783–1784 caused a famine that killed nearly a quarter of the island’s population;[33] the eruption caused dust clouds and haze to appear over most of Europe and parts of Asia and Africa for several months afterward.[34]
    Dettifoss, located in northeast Iceland. It is the largest waterfall in Europe
    Iceland is a member of European Economic Area (EEA), which allows the country access to the single market of the European Union (EU)
    http://en.wikipedia.org/wiki/Iceland

  272. Keith Sketchley says:
    April 28, 2010 at 8:42 am
    ASH CONCENTRATION THRESHOLD

    One of the reasons I said there are so many misrepresentations is the ash concentrations. The Met Office characterized 10 to 130 micrograms per cubic meter as “high concentrations” and “very high concentrations” of volcanic ash in its reports. At these concentrations, it would require an aircraft hundreds of thousands of years in high speed flight and distances well beyond the orbit of Pluto into interstellar space to ingest just one gram of the volcanic ash. Non-aviators should note that aircraft engines and aircraft cannot be operated for hundreds of thousands of years or billions of kilometers without being maintained, retired from service, and scrapped.

  273. stevengoddard:

    Iceland[note 1] ( /ˈaɪslənd/ (help·info)) (Icelandic: Ísland (names of Iceland); IPA: [ˈislant]) is a European island country located in the North Atlantic Ocean[6]

    You are being pedantic. By your line of reasoning, a volcano in Greenland, or the Falklands, also happened in Europe.
    Iceland is located in the North Atlantic. It is cannot possibly be located in Europe because, Europe is the name for a continent, and, last I checked, the definition for the word continent does not include islands 600 miles away.
    If a volcano pops off in Bavaria, it erupted in Europe. A volcano that erupts 1000 miles north east didn’t erupt in Europe, it erupted in Iceland.
    Try this on as many people as you wish: Hand a globe to someone after saying a volcano erupted in Europe, and ask them to point out approximately where that volcano erupted.
    Not even victims of American high school geography classes are going to point anywhere near Iceland.

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