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...

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.

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!

Proved darn useful - STO Radio
 

Hopefully as we see these new regulations come into play, I'd just like to say how useful I found Stockholm Radio's HF service. The staff were most accommodating and helpful in what was probably a busy period for them.

Keep up the great service!

DUFFUS

beware blaming NATS
remember thay only make money en-route if aircraft are flying:ok:

g m c, totally agree! Just like Alaskan Airlines, the airlines of Europe should have approached their regulatory bodies with a safety plan in hand. Hey CAA/JAA, here's the problem and this is our solution in order to operate safely in this new environment. :ok:
Off to Dubai!

To pick up on the point made by green granite and others - what could be a little alarming is that when the 'black' ash cloud suddenly zipped off into the north sea at Warp factor 9 it 'zipped' into an airspace that had been quite clear of 'black' ash on the previous map..

Why all these "discoveries" only after almost 1 month...:confused::ooh:

Even more alarming is the lead-up to the 'jump at Warp 9'.

VA charts for the preceding several days had all shown a consistent progression towards the supposedly-accurate chart for Monday 0600. OK - so maybe the data being fed into the VA modelling software was based on weather forecasts that turned out to be inaccurate.

But hang on a minute.....

Once the actual weather yields real data (wind-speed, mass-air-flows, etc.), then the VA model should be routinely re-run, to correct the effects of incorrect weather forecasts, and then only those results used for further VA movement predictions. Otherwise, there is every likelihood of errors that 'self-amplify'.

It looks possible that this was not done, leading to the chaos on Monday morning: accumulating errors leading to a series of increasingly inaccurate charts, over several days. Then comparison data from an ash research flight (when???) became available, and sudden and massive changes were unavoidable. What other explanation fits the facts?

It would be OK if this was just a bunch of boffins doing basic research. But it seems to me that the Met Office has lost track entirely of the massive cost and other consequences for airlines and customers when errors occur. And quite apart from the noted problem of VA actually being present in the white bits!

Gengis,

So dust is always there, surprise surprise!! I know that because many years ago I flew 1-11's in the Gulf and the leading edges of the wings were sandblasted!!

Surely an analysis of what is on any "collector" device would establish what is sand and low level dust and what is volcanic ash. Correlate that with the condition of the engines and we would be able to get an understanding of the safe level of volcanic dust.

Data is like that

Then that beggars the question isnt the pilot better placed with his/her experience on determining what is safe or not rather than burocrats, innacurate science and a hyped up media?

Pace

Are pilots more expert than the engine manufacturers on what a safe level of ash ingestion is? We have reached the stage we're currently at by having expert analysis, very late given that zero tolerance was the guidance issued 3 years ago. Reading this thread I sometimes wonder whether some people have ever heard of an ancient adage - There are old pilots and bold pilots but there are no old bold pilots.

BD

I would say... not necessarily.

Most pilots won't have any experience with flying in this kind of crud.

Most of the stuff, even in the 'black' zones, is diffuse enough not to be visible even in VMC conditions, so what about IMC and night-time?

What is safe? One flight, two flights, three flights without any obvious engine-related problems? Then your colleague, who takes over the aircraft, hits a bit more ash, and together with the amount you've already unknowingly accumulated, sheds a few turbine blades?

Let's not oversimplify the issue.

CJ

ASH
 

sO NOW WE HAVE A RED ZONE, BEST AVOID ZONE A GREY ZONE DONT STAY TOO LONG ZONE AND A BLACK ZONE OF OMG WE ARE ALL DOING TO DIE ZONE!! WHAT NEXT A DOUBLE YELLOW LINE ZONE OR A ZONE FOR LOADING AND UNLOADING ONLY!!!!!

ITS KINDA GETTING A BIT SILLY NOW DONT WE ALL THINK, IM SURE ASH IS A RATHER NASTY SUBSTANCE TO GET JAMED UP UR PIPES AT 25000 FEET BUT IS IT NOT TIME TO RETHINK THE WHOLE "ZONE" IDEA AND START AGAIN?

no need to SHOUT!

Think before you post, Mad Paddy!
The stuff on the ground in Iceland is the coarse fallout that doesn't float in the air.... so no point in collecting it and playing with it.
The stuff causing the problems is like dust, or talcum powder.
Same like the Sahara sand regularly getting blown over to Europe, which is not sand as you know it on the beach... it's extremely fine dust that can be carried by the wind.
And unfortunately the stuff being blown over from Iceland is not sand dust, it's glass dust, that melts at the temperatures you find in jet engines... unlike sand.

CJ

Madpaddy,
"A lesson for you fenchy. Note the second last sentence please."
Apart from me not being a Frenchy.... is there anything in your "cut and paste" that contradicts what I said?

"Larger rock fragments more than 2 inches across ejected by the explosion typically fall within a few miles of the eruption site. However, wind can quickly blow fine ash away from the volcano to form an eruption cloud. As the cloud drifts downwind from the erupting volcano, the ash that falls from the cloud typically becomes smaller in size and forms a thinner layer."

So collecting ash and debris from the ground a few miles downwind from the volcano for testing is a pretty pointless exercise. The "interesting" stuff is already airborne in the eruption cloud.

CJ

I do feel sorry for Spitzbergen..........

I blogged on this topic a couple of times over the last month. People might be interested in http://www.abnormaldistribution.org/...-volcanic-ash/ , http://www.abnormaldistribution.org/...ic-ash-part-2/ and http://www.abnormaldistribution.org/...-volcanic-ash/

There are pictures of what looks like severe ash damage to a Citation engine circulating on the Internet. They are horrendous. If they are genuine, they will silence our sceptics. Does anyone have a provenance for those pictures?

PBL