New eruption starting in Iceland? (merged)
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There seems to be many comments about airspace closure as per last years event. The big change is that this time around the airlines are responsible for whether they fly or not.
The shakedown after the last occurrence showed that the ATC providers do not have the prerogative to shut down airspace. The airlines are required to submit a risk assessment to the CAA on the levels of ash that they are able to fly through. It would seem most airlines are Cyan - OK, Grey - OK, Red - No Go.
This time around we shall stil have disruption, but a far more fluid situation than last years complete halt. Routes will cease while the threat is present, then reopen.
Another factor is that during the last event, differing forecasting outfits came up with very different results. The UK Met office was deemed to have a very conservative outlook, whilst WSi, which some UK airlines were using, came up with a very different threat level. This year the two forecasts appear to be much better aligned.
Glad I'm on leave though!
The shakedown after the last occurrence showed that the ATC providers do not have the prerogative to shut down airspace. The airlines are required to submit a risk assessment to the CAA on the levels of ash that they are able to fly through. It would seem most airlines are Cyan - OK, Grey - OK, Red - No Go.
This time around we shall stil have disruption, but a far more fluid situation than last years complete halt. Routes will cease while the threat is present, then reopen.
Another factor is that during the last event, differing forecasting outfits came up with very different results. The UK Met office was deemed to have a very conservative outlook, whilst WSi, which some UK airlines were using, came up with a very different threat level. This year the two forecasts appear to be much better aligned.
Glad I'm on leave though!

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London VAAC Projections
At 0600 this morning, it is clear that the UK Met Office Model has overestimated- by a considerable extent, the Southward progression of highly concentrated volcanic ash. This is shown clearly by the 0600 EU Metsat Imagery.
The CAA have admitted that high levels of concentrated volcanic ash have not covered areas of Scotland as envisaged by the model. Instead, they have stated that the ash clouds has moved ''slower than expected'' - which really is not correct.
The southernmost extent of highly concentrated volcanic ash at 0600 was near to the airport of Barra, Scotland, when the London VAAC / UK Met Office Projections indicated highly concentrated ash immediately off the North Coast of Ireland.

Safety is of course paramount at all times - however, the validity and accuracy of the UK Met model must be questioned. There has been some decline in the level of output from the Volcano, according to the latest IMO status reports, which is a welcomed development.
The CAA have admitted that high levels of concentrated volcanic ash have not covered areas of Scotland as envisaged by the model. Instead, they have stated that the ash clouds has moved ''slower than expected'' - which really is not correct.
The southernmost extent of highly concentrated volcanic ash at 0600 was near to the airport of Barra, Scotland, when the London VAAC / UK Met Office Projections indicated highly concentrated ash immediately off the North Coast of Ireland.

Safety is of course paramount at all times - however, the validity and accuracy of the UK Met model must be questioned. There has been some decline in the level of output from the Volcano, according to the latest IMO status reports, which is a welcomed development.

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For what its worth, Kirkwall METAR this morning....
2011/05/24 08:50 EGPA 240850Z 26024KT 3000 VCSH VA FEW008 SCT018 09/06 Q1002 RESHRA
As for the validity / accuracy of the Met Office model, IIRC, other VAAC were requesting access to it after Eyjafjallajökull as it was significantly more accurate than anything they had. However the fact is that forecasting is an inexact science, forecasts will change, and they're based on the best data available at the time of issue, which may not necessarily reflect the actual observations at the time of validity. In other words, forecast does not equal observation. Thats true the world over. In the case of ash, I would imagine it has to show worst case possible spread and concentration - in some places there will be less, in others more.
I'm much more optimistic now than I was yesterday (having not looked too closely at the charts.)
Icelandic Met Office:
2011 | News | About IMO | Icelandic Meteorological office
2011/05/24 08:50 EGPA 240850Z 26024KT 3000 VCSH VA FEW008 SCT018 09/06 Q1002 RESHRA
As for the validity / accuracy of the Met Office model, IIRC, other VAAC were requesting access to it after Eyjafjallajökull as it was significantly more accurate than anything they had. However the fact is that forecasting is an inexact science, forecasts will change, and they're based on the best data available at the time of issue, which may not necessarily reflect the actual observations at the time of validity. In other words, forecast does not equal observation. Thats true the world over. In the case of ash, I would imagine it has to show worst case possible spread and concentration - in some places there will be less, in others more.
I'm much more optimistic now than I was yesterday (having not looked too closely at the charts.)
Icelandic Met Office:
2011 | News | About IMO | Icelandic Meteorological office

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I do wonder at the sanity of some of the posters on here.
Would you prefer that the VAAC model errs on the side of 'Leary and then just hope that no-one accidentally flies through an errant bit of ash?
Old saying," i'd rather be on the ground wishing that I was up in the air, than up in the air wishing that I was on the ground"
Would you prefer that the VAAC model errs on the side of 'Leary and then just hope that no-one accidentally flies through an errant bit of ash?
Old saying," i'd rather be on the ground wishing that I was up in the air, than up in the air wishing that I was on the ground"

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As for the validity / accuracy of the Met Office model, IIRC, other VAAC were requesting access to it after Eyjafjallajökull as it was significantly more accurate than anything they had. However the fact is that forecasting is an inexact science, forecasts will change, and they're based on the best data available at the time of issue, which may not necessarily reflect the actual observations at the time of validity. In other words, forecast does not equal observation. Thats true the world over. In the case of ash, I would imagine it has to show worst case possible spread and concentration - in some places there will be less, in others more.
I think that perhaps the industry would be better served right now with dual use of real time analysis and NWP modelling, as opposed to ridigly adhering to the NWP modelling. A mix of both will yield the best outcome, whilst still maintaining safety for all.
Safety trumps all other factors, but it is equally important to ensure that when viable - flight operations should continue.

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'Ash Plotter' neat idea...
I was just surfing the web looking for more info about the current situation on the eruption and I stumbled across this site 'aviolinx.com'.
They offer an application that plots the latest ash cloud co-ordinates and compares it with your days flying program (stored flight plans). Probably quite useful for an Ops department for planning purposes...
They offer an application that plots the latest ash cloud co-ordinates and compares it with your days flying program (stored flight plans). Probably quite useful for an Ops department for planning purposes...

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I do wonder at the sanity of some of the posters on here.
Would you prefer that the VAAC model errs on the side of 'Leary and then just hope that no-one accidentally flies through an errant bit of ash?
Old saying," i'd rather be on the ground wishing that I was up in the air, than up in the air wishing that I was on the ground"
Would you prefer that the VAAC model errs on the side of 'Leary and then just hope that no-one accidentally flies through an errant bit of ash?
Old saying," i'd rather be on the ground wishing that I was up in the air, than up in the air wishing that I was on the ground"
Obviously you didn't read my post properly did you? I said safety is paramount, however operations should NOT remain suspended if Volcanic ash has not entered various areas of airspace as previously envisaged.
I'd prefer the use of the VAAC model combined with real time analysis as above. It was the rigid adherence to the NWP modelling last year that wrought havoc.

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Frightened laymen.
I wonder at the professions of many posters who obsess about safety. They are clearly not professional pilots. We who fly for a living do not feel the need to post sweeping generalisations about safety being paramount, BECAUSE WE KNOW AND UNDERSTAND THIS.
As this site is for professional pilots primarily, will the wimps who keep posting the message that it is better not to fly rather than take the slightest risk please shut up? Flying always involves a small measure of risk, and will always be so. We never knowingly take unnecessary risks, whether at the behest of our companies or passengers, or indeed government authourities. This is our creed.
As this site is for professional pilots primarily, will the wimps who keep posting the message that it is better not to fly rather than take the slightest risk please shut up? Flying always involves a small measure of risk, and will always be so. We never knowingly take unnecessary risks, whether at the behest of our companies or passengers, or indeed government authourities. This is our creed.

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Aaaaasshhooo!!!!
Am I missing something here or does it appear that the people who are saying it's ok to fly through reported ash concentrations are desk pilots, who will be around to defend themselves and collect their vast pensions after the Accident Investigation??!!
Even if it doesn't get as far as that, there'll still be sackings when airlines have to shell out for the refurbishing of power plant which have suffered subtle "glassing" of the hot ends and abrasion of the cool ends, which wasn't noticed at the time.
Quite how I'm supposed to assess micrograms of particles per cubic metre whilst whistling through it at 480kts TAS has not yet been clarified. Also as flight crew I'm expected to perform an "enhanced pre & post flight inspection" of my shiny craft and certify same in the tech log, though I can't be trusted to perform minor maintenance tasks which I formerly could do, before the Eurocrats started to pontificate.
Also my B73NG manufacturer sourced QRH says I have to select Wing Anti-Ice on as I assess the 0.004gms/cubic metre is getting too much for comfort, yet several pages later it says don't do this above FL350 as I'll probably get a dual bleed trip-off and lose pressurisation. Can anyone with a hotline to Mr Boeing or Mr CFM cast any light on this?!
Commercial pressure once again dominates and the "Tombstone Imperative" waits to collect more bodies and wreckage. Why does the Titanic keep invading my by now confused thoughts??
But then what do I know about aviation, I haven't got a MBA qualification or some Air Transport degree? 40 years and 18,000 hours since first my sweaty little palm first gripped the column of a Chipmunk does not qualify me even to satisfy HR that I'm able to do aviation maths, understand and occasionally express English and that I'm a jolly good sane person and fit for the job!!!
Ohmigawd, that darkened room beckons again, and it's not even midday yet!!!!
Even if it doesn't get as far as that, there'll still be sackings when airlines have to shell out for the refurbishing of power plant which have suffered subtle "glassing" of the hot ends and abrasion of the cool ends, which wasn't noticed at the time.
Quite how I'm supposed to assess micrograms of particles per cubic metre whilst whistling through it at 480kts TAS has not yet been clarified. Also as flight crew I'm expected to perform an "enhanced pre & post flight inspection" of my shiny craft and certify same in the tech log, though I can't be trusted to perform minor maintenance tasks which I formerly could do, before the Eurocrats started to pontificate.
Also my B73NG manufacturer sourced QRH says I have to select Wing Anti-Ice on as I assess the 0.004gms/cubic metre is getting too much for comfort, yet several pages later it says don't do this above FL350 as I'll probably get a dual bleed trip-off and lose pressurisation. Can anyone with a hotline to Mr Boeing or Mr CFM cast any light on this?!
Commercial pressure once again dominates and the "Tombstone Imperative" waits to collect more bodies and wreckage. Why does the Titanic keep invading my by now confused thoughts??
But then what do I know about aviation, I haven't got a MBA qualification or some Air Transport degree? 40 years and 18,000 hours since first my sweaty little palm first gripped the column of a Chipmunk does not qualify me even to satisfy HR that I'm able to do aviation maths, understand and occasionally express English and that I'm a jolly good sane person and fit for the job!!!
Ohmigawd, that darkened room beckons again, and it's not even midday yet!!!!


one green and hoping (post #79)
I seem to recall the pilot mentioning that volcanic ash didn't appear on weather radar, and hadn't been informed of the eruption from ATC.
The investigations eventually led to...
I seem to recall the pilot mentioning that volcanic ash didn't appear on weather radar, and hadn't been informed of the eruption from ATC.
Because the ash cloud was dry, it did not show up on the weather radar, which is designed to detect the moisture in clouds.
It was recognised that there was an issue following the incident in 1982 with the British Airways Flight 9 and therefore the ICAO established the Volcanic Ash Warning Study Group in 1982. Due to the difficulty in forecasting accurate information out to 12 hours and beyond the VAAC were set up by the ICAO as part of IAVW.
