Ash clouds threaten air traffic

[topper3]

I think the depth at Katla was actually 9.5km with a magnitude of -0.2 (negative magnitude?) Makes no sense really.

[slf99]

Flybe first to adopt CAA relaxed rules

Pity the Flybe e-mail I've just received (as sent to all its frequent flyers) is entitled "Flybe welcomes new CAA fules for Q400 flying".

Shurely some mistake, as any fule knoeth.... or perhaps not?

[oceancrosser]

I have in front of me a report from 2005 by the very scientists that are currently studying this eruption. This is a risk assessment of probability of eruptions and subsequent flooding (which is the major threat). I have property on the outskirts of the most extreme flooding area.
I could post the article here, but it is in Icelandic so it is only of use to few people.
Eyjafjallajökull is known to have erupted 4 times in the last 1500 yrs (~500, ~920, 1612 and 1821. Katla is known (and estimated) to have erupted about 25 times since ~700 (this includes possible minor eruptions that never made it through the glacier). Of this number, 6 are considered to have been major. The interval between major eruptions 150-300 years. The last major one was in 1918.
Eyjafjallajokull and Katla have erupted at a similar time 3 times, but the only time it is known Katla was following was in 1823. It is apparently not documented which went first in ~920 and 1612.
So hold your southern horses for a while. Everything moves around here, and does so all the time. We are pretty used to it. I have watched and flown around about 8 eruption in my aviation life. We even used to do sightseeing flights around the eruption.
Prof.Haraldur Sigurdsson who was on 60 minutes recently, and is renowned around the world of volcanology considers this Katla angle "a media fever". Is that where you are from? Your profile certainly does not indicate that you are an aviation professional.

The thing is that this is the first sizeable eruption in this part of the world since the start of modern aviation. Todays aviation industry needs to learn (and fast) how to live with it, and get as close to normalcy as possible.

Oh and yes the eruption was spectacular to watch on Friday and Saturday this weekend from my country property, 30 miles from the crater.

[GarageYears]

Oceancrosser, I certainly defer to your local knowledge, but I would also refer to a number of knowledgeable vulcanologists that I am in contact with. While their science seems to border on voo-doo at times, their consensus is that Katla is due and will likely "pop" (my words, not theirs) very shortly (qualified to mean somewhere within 0 to 2 years from right now). I guess time will reveal who is right.

I certainly hope you and your property remain safe, and I would add am quite envious of what are no doubt amazing views.

- GY

[22 Degree Halo]

Better to be safe than sorry, huh?

SEVIRI BTD

Ends at the current day ^

[petitb]

petitb

itsresidualmate.

"So far I've not found any evidence of ash damage in all the aircraft I've inspected (northern european regional routes). I've asked a lot of my colleagues in other airlines if they've found any evidence of ash damage or if they've heard of it being found :- Nothing. Not one engineer I've contacted has found or known of anyone finding damage. Now I don't claim to know every engineer in Europe, but it does seem that ash damage is thin on the ground (or the blades). I think that any maintenence cost saving from not flying is going to be dwarfed by the loss of revenue."

Would this by any chance be the result of not flying through ash, in other words the restrictions are working ?

[sky9]

I would have thought some clever scientist would have come up with a double sided sticky patch that samples the actual dust flown through by the aircraft and records it for monitoring and analysis.

[Genghis the Engineer]

Originally Posted by sky9

I would have thought some clever scientist would have come up with a double sided sticky patch that samples the actual dust flown through by the aircraft and records it for monitoring and analysis.

Problem is, you'll get all the low level dust on the way up and down as well, which is always there.

G

[BOAC]

Gengis - the key is in "and records it for monitoring and analysis." This dust/ash is, we are told, quite different to both 'normal' volcanic ash and, say, something like Saharan desert dust - surely it is possible to separate? Why is it not possible also to have a sampler which can be isolated until needed - a simple motorised door would do? This part of the world is going to have come up with something PDQ as it looks as if the problem is with us for a while.

[Pace]

Acceptable Ash Levels Doubled

I see from today that the acceptable Ash levels have been doubled with the Airlines calling for a tripling of those levels.

Pick a number from 1 and 10 if it doesnt work start again

All sounds very scientific

Pace

[brooksjg]

As has already been discussed, aircraft already have air filters that (it is said) can be examined for VA particles - all you need is a microscope and possibly a very precise weighing machine. There's also oil from the engines, which is a very accurate tell-tale for larger volumes of nasties the engine might had through it since last oil-change. We've not heard much detail about what's actually being done with this existing evidence, however.

[brooksjg]

VA Forecast accuracy

As it happened, I was paying closer attention to the Met Office Red/Black composite graphics yesterday and was surprised to see the supposed Ash Cloud with a large Black area extending southward nearly to LGW on the 0600 forecast suddenly retreat at the speed of light!! The new southern boundary then went only as far south as Central Scotland. I guess I should have only relied on the less-detailed the official VA advisories - these did NOT show any such sudden change!

Explanations for this came there none - how people who rely on this stuff for flight planning are supposed to make good decisions beats me!.

Just pre-announcement of yet another category of ash cloud flyable under yet more conditions, risk-assessments, etc.

Then, BBC Newsnight covered the topic of VA. Aha! I thought - now the UK public will get some clarity. Wrong. All we got was Susan Watts delivering a deeply-flawed piece (with an incorrectly labelled diagram of an engine) about the effects of VA.

[itsresidualmate]

Petitb;

"

Would this by any chance be the result of not flying through ash, in other words the restrictions are working ?

I've got an elephant scaring crystal in my garden, it must work because I haven't seen any elephants in there!!
With the amount of civil air flights and the number of inspections we're doing I find it hard to believe that the threat is as real as the CAA/EASA/Government make out. Where's the evidence of contamination? Have no engineers found problems? To ground flights there must surely be a current danger to aircraft, I just don't believe there is. Of course flying through a volcanic plume will probably ruin your day, but flying around hundreds of miles away when it's dispersed? Maybe some accelerated wear and tear but the plane ain't going to fall out the sky!

http://www.wwiivehicles.com/usa/airc...esuvius-01.png

[sabenaboy]

@itsresidualmate:

you wrote:

With the amount of civil air flights and the number of inspections we're doing I find it hard to believe that the threat is as real as the CAA/EASA/Government make out. Where's the evidence of contamination? Have no engineers found problems? To ground flights there must surely be a current danger to aircraft, I just don't believe there is. Of course flying through a volcanic plume will probably ruin your day, but flying around hundreds of miles away when it's dispersed? Maybe some accelerated wear and tear but the plane ain't going to fall out the sky!

I agree with you on this, itsresidualmate.

petitb wrote:

"So far I've not found any evidence of ash damage in all the aircraft I've inspected (northern european regional routes). I've asked a lot of my colleagues in other airlines if they've found any evidence of ash damage or if they've heard of it being found :- Nothing. Not one engineer I've contacted has found or known of anyone finding damage. Now I don't claim to know every engineer in Europe, but it does seem that ash damage is thin on the ground (or the blades). I think that any maintenence cost saving from not flying is going to be dwarfed by the loss of revenue."

Would this by any chance be the result of not flying through ash, in other words the restrictions are working ?

Even though I also believe that authorities have overreacted, I have to agree with petitb that the fact that no damage (or ash) has been found, proves absolutely nothing. Your argument does indeed resemble very much the elephant scaring crystal in our garden, I'm afraid.

As Pace has stated before: a better argument is that there's never been an incident outside of ash concentrations visible to the naked eye. (Or would have been visible in daylight VMC) (Anybody reading this: pls don't bring back the NASA DC8 case again )

Best regards,
Sabenaboy

[infrequentflyer789]

Originally Posted by brooksjg

As it happened, I was paying closer attention to the Met Office Red/Black composite graphics yesterday and was surprised to see the supposed Ash Cloud with a large Black area extending southward nearly to LGW on the 0600 forecast suddenly retreat at the speed of light!!

Explanations for this came there none .

Explanations in the press now:

The ash cloud that never was: Inaccurate Met Office forecast causes airport chaos for 50,000 | Mail Online

A CAA spokesman said: ‘The Met Office model was predicting ash which was not there when the test
flights were done. We have asked the Met Office why their forecast model showed something which
was not subsequently backed up.’

Not entirely sure why the CAA regard an inaccurate Met Office forecast as something out of the ordinary, but...

The second concern is that clearly if ash is not present where the forecast says it is, it may also actually be present where the forecast says it's not. I hope that at the pointy end, the presence of white on the charts is not being substituted for the mk1 eyeball and see and avoid.

[MPN11]

Perhaps someone will regenerate an old concept to defeat long-term ash problems?

XC-99

Slow but safe?

[green granite]

What concerns me is if the computer model is inaccurate as it appears to have been in this case, could it get it wrong the opposite way round and end up with aircraft flying through an ash cloud not predicted.

[Mir]

What concerns me is if the computer model is inaccurate as it appears to have been in this case, could it get it wrong the opposite way round and end up with aircraft flying through an ash cloud not predicted.

From Eurocontrol :

"These charts enable States to establish NO FLY zones or other restrictions where necessary. Ongoing work by the UK Met Office and the UK CAA has confirmed the effectiveness of the model used to determine the areas where ash concentration could be above engine tolerance levels. For that reason, the 60 nautical mile "Buffer Zone" which was initially added has been removed from charts published as from 11-1200 UTC. States retain the prerogative to add the 60nm buffer if they believe it is necessary to do so. "

So apparently the model is good enough to remove the 60nm buffer zone, but so faulty that it closed a large area around London yesterday...

Really hope that the VAAC computer is set to "Over cautious"-mode and not just calculating wrongly as green granite is wondering too...

[Duffus]

Would those who make the sweeping closures of airspace so readily do so if they had to pick up the bill that the airlines have had to do.
I do not believe that the closures last month would have been so prolonged if Nats/Met Office/Government had to pay for all those stranded passengers enforced extra costs.

[atlast]

Alaskan Airlines has been dealing with operations in and around volcanic activity for years but I believe they operated on a basic see and avoid basis combined with visual tracking of the ash cloud. Day VFR mostly until and this was approved by the FAA and all the tracking information was made available to all the airlines operating in and out of Anchorage. Undoubtedly some ash was ingested but low level amounts. I wonder why no-one in Europe made a phonecall and just said,
" Hey, kinda different for us, but we've had this volcano go off and we have no procedures in place for these kind of operations. Can you help us out? "

In aviation, as a sweeping generalization, it's nearly always happened before!

Oh well, back to reality, about to leave the ash and fly into the sand!