Ash clouds threaten air traffic
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The latest charts look like this. Strange that predictions change so quickly. Or would there be someting else going on?
Last edited by sabenaboy; 17th May 2010 at 12:35. Reason: Chart deleted. "itwasme" posted it a few seconds earlier.
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The chart is in fact a Rorchsach Blot test to determine how you voted at the last Election. If you look very closely, you can see a silhouette of Gordon Brown leaving No 10.
Right, time for my pills
Right, time for my pills
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Errrr - the 1200 chart shows that the Black area that extended South virtually to LGW up to 0600 this morning (and was predicted to hang around until tomorrow at earliest) has now moved (VERY) rapidly North and shrunk a lot, so the southern boundary now runs through central Scotland.
This is crazy! Clearly the VA cloud could not really move at anything like that rate between 0600 and 1200 the same day, even in gale-force southerlies (which we ain't got anyway). Furthermore, the behaviour of VA clouds does not include ash suddenly falling to earth, which is the only other simple explanation for the change.
So what's going on? Reworking of the modelling software? Redefinition of the input data (which was perhaps overly pessimistic up until this morning) or duff / very fast-changing (??) weather / mass airflow data?
You tell me!
Until it's clear how this change suddenly occurred, it seems that VACC forecasting has a bit of a credibility gap to fill (and maybe plenty of spare ash to fill it with!).
This is crazy! Clearly the VA cloud could not really move at anything like that rate between 0600 and 1200 the same day, even in gale-force southerlies (which we ain't got anyway). Furthermore, the behaviour of VA clouds does not include ash suddenly falling to earth, which is the only other simple explanation for the change.
So what's going on? Reworking of the modelling software? Redefinition of the input data (which was perhaps overly pessimistic up until this morning) or duff / very fast-changing (??) weather / mass airflow data?
You tell me!
Until it's clear how this change suddenly occurred, it seems that VACC forecasting has a bit of a credibility gap to fill (and maybe plenty of spare ash to fill it with!).
Pilot of the Airwaves
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Possibly because G-LUXE has been flying a volcano ash patrol this morning and hasn't found ash where the computer previously said there was.
If so, were all the airport closures in the last 24 hours based on duff info?
If so, were all the airport closures in the last 24 hours based on duff info?
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Perrin
Its a good question "why do Ryanair seem to cancel first" i can only assume that they make more or lose less by bunching people on to subsequent flights? plus many will simply not bother to reclaim their money and a lot of tickets will have been sold at below cost in what is a shoulder period, for sure you can bet they wont have done it to increase their costs.
If you had two aircraft flying with say a 130 paxs and half were on "sale" tickets you could probably improve the yield by flying the next day with one full aircraft.
If you had two aircraft flying with say a 130 paxs and half were on "sale" tickets you could probably improve the yield by flying the next day with one full aircraft.
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These massive changes to the forecasts every six hours are causing havoc - frontline staff getting sh*t from pax holding laptops and pointing at these VAAC charts ........... so unprofessional
So what's going on? Reworking of the modelling software? Redefinition of the input data (which was perhaps overly pessimistic up until this morning) or duff / very fast-changing (??) weather / mass airflow data?
I'd guess. We have a new government after all.
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....and because of the 'very fluid VA forecast situation', it looks like LGW has probably got lots of SLF sitting around getting cross but no aircraft to load up!!! On Radar Virtuel, it looks like Sleepy City!
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They should do the charts and closures every 2 hours or so. That way a 12 hour closure may only last 4 or 6 hours. It seems if the ash is going to be too thick at 6PM to 10PM they close the airspace at 1PM to 1AM the next day.
Katla waking up?
Just to add more fun... there was an earthquake below the Katla volcano within the last 12 hours. If Katla wakes up (which it surely will based on history) all the current fun and games will look like kiddy stuff.
- GY
- GY
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Katla little earthquake
Well said, in fact this webcam
Katla | Ríkisútvarpið vefur
is the most important to watch right now!!!
If the eruption of Katla starts we all better forget about flying tubes and forums, instead we must run to the nearest supermarket and immediately stock on food, water, etc.
Katla | Ríkisútvarpið vefur
is the most important to watch right now!!!
If the eruption of Katla starts we all better forget about flying tubes and forums, instead we must run to the nearest supermarket and immediately stock on food, water, etc.
The latest FODCOM from the CAA is at http://www.caa.co.uk/docs/33/FOD201018.pdf
Introduces Time Limited Zones which seem to allow some flight for short periods in low concentrations of Ash by AOC holders.
Introduces Time Limited Zones which seem to allow some flight for short periods in low concentrations of Ash by AOC holders.
Ryanair claims the VAAC's forecasting is not only unreliable but "substantially fictitious".
"It would appear that there is one model for air safety for all other UK airports, but when it threatens the opening of Gatwick and Heathrow, these [forecasts] are simply ignored," it adds.
"Today's decision to re-open Gatwick and Heathrow airports, despite the fact that this imaginary black cloud or 'no-fly' zone is hovering right over Heathrow and Gatwick, proves that the [VAAC charting] no longer retains any credibility or confidence within the airline industry."
"It would appear that there is one model for air safety for all other UK airports, but when it threatens the opening of Gatwick and Heathrow, these [forecasts] are simply ignored," it adds.
"Today's decision to re-open Gatwick and Heathrow airports, despite the fact that this imaginary black cloud or 'no-fly' zone is hovering right over Heathrow and Gatwick, proves that the [VAAC charting] no longer retains any credibility or confidence within the airline industry."
Ryanair noticed it. Either the danger or the precaution is fiction....
Katla waking up?
--------------------------------------------------------------------------------
Just to add more fun... there was an earthquake below the Katla volcano within the last 12 hours. If Katla wakes up (which it surely will based on history) all the current fun and games will look like kiddy stuff.
--------------------------------------------------------------------------------
Just to add more fun... there was an earthquake below the Katla volcano within the last 12 hours. If Katla wakes up (which it surely will based on history) all the current fun and games will look like kiddy stuff.
There have been instances where Katla has erupted shortly after Eyjafjallajokull, but it is by no means a regularity. Such eruptions have tended to be on the smaller side. The indicated quake you referred to appears to be a fluke. It is shown at 200 meters above the surface and a quality (of measurement) index of 37%. This is unedited data and gets corrected all the time. Don´t read to much into it.
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New rules
The CAA change the rules again.....press release:
Link here
Further progress made to safely minimise ash disruption
The UK Civil Aviation Authority (CAA) today reports a positive outcome from discussions with airlines, regulators, and aircraft and engine manufacturers resulting in new measures to reduce airspace closures caused by volcanic ash. These new measures will be available from midday tomorrow.
A new area of operations can now be introduced that creates a ‘Time Limited Zone (TLZ)’ between the black ‘No Fly Zone (NFZ)’ and the red ‘Enhanced Procedures Zone (EPZ)’. Aircraft and engine manufacturers, based on new research and analysis, have agreed that it is safe to allow operations in the new zone for a limited time at higher ash densities than is currently permitted.
To operate in the new zone airlines need to present the CAA with a safety case that includes the agreement of their aircraft and engine manufacturers. UK airline Flybe is the first to achieve this and will therefore be able to use the new zone from midday tomorrow.
This means that areas of our airspace that would have previously been closed can safely open, further minimising flight disruption.
The UK Civil Aviation Authority (CAA) today reports a positive outcome from discussions with airlines, regulators, and aircraft and engine manufacturers resulting in new measures to reduce airspace closures caused by volcanic ash. These new measures will be available from midday tomorrow.
A new area of operations can now be introduced that creates a ‘Time Limited Zone (TLZ)’ between the black ‘No Fly Zone (NFZ)’ and the red ‘Enhanced Procedures Zone (EPZ)’. Aircraft and engine manufacturers, based on new research and analysis, have agreed that it is safe to allow operations in the new zone for a limited time at higher ash densities than is currently permitted.
To operate in the new zone airlines need to present the CAA with a safety case that includes the agreement of their aircraft and engine manufacturers. UK airline Flybe is the first to achieve this and will therefore be able to use the new zone from midday tomorrow.
This means that areas of our airspace that would have previously been closed can safely open, further minimising flight disruption.