Ash clouds threaten air traffic [Archive] - Page 12

The SSK

11th May 2010, 20:54

Tomorrow's midday chart shows 'almost nothing' emerging from the volcano. Has it quietened down?

I was intrigued today to discover that the task of producing the charts is assigned to the VACC in which the volcano is located. The London VACC is actually a very small one, consisting of Iceland and the British Isles, full stop.

The rest of Europe, all of Africa, the Middle East, half of Russia and even India, falls within the Toulouse VACC. But as it's not 'their' volcano, they can only play a secondary, advisory role to London. Even though it's 'their' airspace which is being closed. Remarkable too that the London VACC charts showed no-fly zones in France at the weekend which the French, acting on their own data which included test flights by Air France, chose not to implement.

topper3

11th May 2010, 21:41

"Tomorrow's midday chart shows 'almost nothing' emerging from the volcano. Has it quietened down?"

Definitely hasn't quitened down, in fact the eruption became more explosive again this afternoon. There's some very usefull updates about the eruption on the Iceland Met Office website.

I suspect that the low pressure over Iceland tomorrow and the associated calm winds will cause the plume to gather and spread over the eruption site rather than being blown out to sea as we've been seeing previously. It'll be interesting to see how the passing depression re distributes the ash cloud :8

BillS

12th May 2010, 00:38

It may not have quietened down (http://www.nrk.no/nyheter/verden/1.7120298) but yesterdays report (http://en.vedur.is/media/jar/Eyjafjallajokull_status_2010-05-10_IES_IMO.pdf) suggested
Tephra fallout: Ashfall reported at Drangshlíð and Skarðshlíð almost continuously for the last 24 hours. The ash is rather coarse, estimated by the farmers to be ~2-3 mm.
Very different from the early very fine ash!

peter we

12th May 2010, 07:29

Remarkable too that the London VACC charts showed no-fly zones in France at the weekend which the French, acting on their own data which included test flights by Air France, chose not to implement.

France did implement a no fly zone, so I suspect they were simply asleep, rather than remarkable.

threemiles

12th May 2010, 13:55

From sat24.com:
Wind changed from NorthEast to NorthWest since a few hours and new plume heading towards Faroer and Scotland. Over Scotland within 24 hours if speed remains. Interesting to know what's gonna happen then.

dublindispatch

12th May 2010, 14:05

Can I just ask someone to recap a few points for me as the goal posts seem to change daily.

1/ The charts are a bit like the TV game Bullseye! Stay out of the black and stay in the red you get nothing in this game for two in a bed as in is the black a total total no go zone and the red is go at your own risk?.

2/Why was the altitude of SFC to 20000 chosen and not higher or lower ?

3/Is 20000 some magic height that the industry has chosen or is it based on average ash height etc?

4/Are airspace closures for all flights or just commerical flights?

5/ Has the same type of airspace closures happened anywhere else outside Europe/North Africa??

Nearly There

12th May 2010, 14:41

Just to add to question 1/ above, how long can you stay in the red for? briefly? can you hold in it? surely accumulative damage starts to play a part..

Suzeman

12th May 2010, 16:44

Can someone from an airline planning dept or ATC please explain what is going on to a confused SLF like myself.

In the last few days a number of transatlantic flights to and from Spain have been routing North South and vv across the UK going up towards 60 North no doubt to avoid the ash cloud. One day AA's MAD- JFK B767 was even reported as going over NE over Cherbourg, London and Ipswich before turning NW over the N Sea and then running parallel to the UK East Coast about 100 miles offshore. Also reported N-S or vv over the UK are transatlantic TAP flights and Aeromexico/ Mexicana flights from Madrid.

At the same time most AF transatlantics, along with KL and LH (both ETOPS twins and 747s) seem to have been routing North just off the Noreweigan coast

During all this disruption, a small number of transatlantic flights mostly BA have been reported as coming off the Ocean / going oceanic over Cork and Shannon.

If the ash cloud area was stopping all these other flights going on their normal "best route", how come these flights seemed to come through the affected area.:confused:

Any explanation gratefully received!

Suzeman

OFSO

12th May 2010, 17:24

I would guess, altitude. Waiting at GRN yesterday for flight to leave, (and it was subsequently cancelled due to 'volcanic ash cloud' starting at FL20) we could hear and see trans-continental aircraft flying way overhead, where we live that's usually the Paris CdG to Africa run, obviously above the top level of the cloud at FL30.

The SSK

12th May 2010, 18:28

dublindispatch:
Is 20000 some magic height that the industry has chosen or is it based on average ash height etc?

'The industry' has little or no input to this process - more's the pity.
Ifit can be convinced that this process is scientifically valid (which at the moment is not the case), 'the industry' would rather have charts with more and probably different altitude segments, to help them make their own operational (not commercial) judgement about whether to fly under, over or around.

doublesix

12th May 2010, 18:53

I posted earlier about bringing my parents home from MAN after their Thomson flight to Tenerife was indefinately delayed yesterday.
They were going on holiday with friends who were flying to Tenerife with Monarch from Gatwick, similar time yesterday. Guess what, they arrived in Tenerife 8pm last night. How? Did Monarch fly through the ash? I presume not. Also yesterday evening I looked at Manchester departures and flights from mid afternoon were showing as having left!!
Am I being cynical in thinking Thomson may have used the plane my parents were due to fly on for another service.
Anyway they are at the airport now due to depart at 20.50hrs tonight. 36hrs late.

jonseagull

12th May 2010, 20:06

Don't think you're being overly cynical but all airlines are having different problems posed by the current conditions and are having to deal with their own particular disruption in their own way. It's not the airline trying to victimise your parents, or anyone elses for that matter, they're just trying to cope as best they can.

OFSO

12th May 2010, 20:41

I just just glanced at this...

Am I being cynical in thinking Thomson may have used the plane my parents were due to fly on for another service.

.....because I saw a Thomson taking off from GRN about 12:00 local today, and can't remember having seen one there at that time before....

To be fair there's a lot of disruption and the airlines are doing their best.

sunny11410

12th May 2010, 20:58

Just to add to question 1/ above, how long can you stay in the red for? briefly? can you hold in it? surely accumulative damage starts to play a part..

Not 100% sure but the red coloured area ( UK MET Office ) will mostlikely illustrate the so called Zone 2 while the black coloured is the Zone 1.

Zone 1: Limited No-Fly Zone is an Area with a High Density Volcanic Ash Contamination. A "No fly zone" - which includes the main area/core of the volcanic fallout, with an additional buffer zone.

Zone 2: Potential Contamination Zone is an Area with a Low Density Volcanic Ash Contamination. An area outside Zone 1 where flying can be conducted when actual conditions, risk assessment and test(s) can establish, that flights can be conducted at an acceptable level of safety and requires prior permission from the operators Authority.

At least Icelandic AOC holders have to apply for such permission from the ICAA. Prior such an application you have to set up several operational & maintenance related procedures ( e.g. recommendations from the TC holders ). In addition to the daily checks i.a.w. EASA SIB No: 2010-17, the ICAA for example requires, when an aircraft has been operated for a maximum time of three accumulated flight hours in "Low density Ash" (Zone 2), an inspection in accordance with aircraft and engine manufacturer guidelines for inspection after flying in volcanic ash shall be performed.

Not sure how other authorities are handling that and if they have these accumulated 3 hours restriction in place as well.

However, GE for example says for Zone 2 ( greater than 2E-4 grams/meter cubed, but less than 2E-3 grams/meter cubed predicted zone, "Enhanced Procedures Zone" ): There are no additional maintenance or operational procedures required to ensure safe operation!
RR and PW have a set up a little bit different recommendation.

While the engine OEM's are not calling for any time limitations when flying thru Zone 2, the local authorities are handling that obviously different. So your question can't be answered with a "standard statement".

BTW: the local TV station RUV made a nice video clip last evening from the local at eruption side:

Gos í fullum gangi - myndskeið | Ríkisútvarpið vefur (http://www.ruv.is/frett/gos-i-fullum-gangi-myndskeid)

To see the clip, click on "Horfa á myndskeið"!

Currently we have again massive ash fall in the south east and all the glory can be watched here :

Eyjafjallajökull frá Hvolsvelli (http://eldgos.mila.is/eyjafjallajokull-fra-hvolsvelli/)

Also a good overview in regards to the actual seismicity( Eyjafjallajökull vulcano is at the glacier in the south ) can be found here:

Iceland Meteorological office - Earthquakes Iceland (http://en.vedur.is/earthquakes-and-volcanism/earthquakes/)

( not sure if those links have been posted already )

Greetings from Iceland

Sunny :)

Agaricus bisporus

13th May 2010, 09:35

Zone 2 greater than 2E-4 grams/meter cubed, but less than 2E-3 grams/meter cubed

To put that into perspective a CFM56 with a mass flow of 1000cum/sec will be ingesting between 0.2 and 3.0 g/sec

Or 12 - 180g/min

or 720 - 10,800g/hr

Even though the great majority of that goes through the fan and not the core it won't take long to build up accretions if only a thousandth part of that gets to stick...

OFSO

13th May 2010, 09:42

Noticed this morning we have light gray/brown, slightly "fluffy" deposits on our windowsills here at 3ºE 42ºS. (Catalunia). Never seen this before. It is NOT the other usual bane of our lives here, dust from the sahara or spring pollen. Suspect it's ash but que saps ?

I just posted a photo of these deposits but on JB......

brooksjg

13th May 2010, 09:47

BOAC

13th May 2010, 11:03

I suspect a lot of it is inside the turbine blades as commented by many and will make itself evident in due course with reduced engine life and the odd blade falling out of the back with an alarming banging noise?

lomapaseo

13th May 2010, 13:32

It's still a great mystery to me where the VA evidence is going!
Under present (new) rules, it would be very unusual for an engine to run for as long as an hour in an ash zone or around the edges where it can be assumed there would have to be some ingestion. Nevertheless, if the permitted worst case is 10 (TEN) kilos per hour through the front of the engine, there would have to be some traces left, somewhere, from shorter encounters.
So where is it??
Or are people not yet looking in the right places?

Not much unique about volcanic ash particles other than their melting points compared to surface dirt. So with all the sucking of engines for years on-the-wing, not much accumulations are found within the engine. The coarse stuff hugs the outer walls and goes out the rear after slowly eroding blades. The fine stuff flows freely through the cooling holes and finally ends up out the rear of the engine. The in-between stuff either dirt or ash may get stuck in the cooling holes and result in some annomally in a single engine some day.

Lots of data available to the big operators to put this in perspective so ask them.

bvcu

13th May 2010, 18:07

Recently boroscoping a Trent 800 in the sandpit and quite distinctive red sand particles adhering to leading edge of final stages of HP comp blades which dont seem to give problems , but would imagine anything else , i.e ash would possibly do the same .

brooksjg

14th May 2010, 08:52

....not much accumulations are found within the engine. The coarse stuff hugs the outer walls and goes out the rear after slowly eroding blades. The fine stuff flows freely through the cooling holes and finally ends up out the rear of the engine. The in-between stuff either dirt or ash may get stuck in the cooling holes....So: there are two completely different situations:

1 - where there's enough VA (especially large particles) coming through the combustion chamber, getting hot enough to melt and coat the first stage blades and vanes with a layer of glass-like material, and therefore cause rapid blade failure and/or the engine actually stopping due to disruption of gas flows. No-one has yet identified (here, at least) a ball-park figure for ash density where this starts to be a possibility but it seems that it's going to be at least one, if not two, orders of magnitude greater than the current Black area average.

2 - where there's NOT enough VA melted inside the combustion chambers to permanently coat blades to a dangerous level and any VA that goes through the cooling system is fine enough to go through and not get stuck inside galleries or holes. From what has been discussed here, unless an engine has already been exposed to a lot of VA, any ash that does get into the cooling system will not go above its melting point (ie. the cooling system will still be doing its job!) and will therefore continue through the blade holes and slots, and out the back with relatively little effect.

Given the nature of the current Iceland eruption, the VA particles will be very small (otherwise they wouldn't float around for so long). If / when the ice and water around the vents and leaking into the volcano has mostly gone, any VA particles still being formed will be much larger and will therefore fall to ground / sea much more quickly and become of little significance (eg.) above FL10 and /or more than 100 miles from Iceland.

These (under-informed) conclusions are supported by the lack of published evidence of VA discovered inside engines during the current Iceland situation. There may of course be other evidence and other people who already know very different!

The SSK

14th May 2010, 15:43

UK Met charts show the FL0 - FL200 no go zone over the UK Monday, much of Germany could be out Mon/Tue and into Wed :eek::eek::eek:

DOOBIE

14th May 2010, 15:57

Where do you find that please SSK
Thanks

peter we

14th May 2010, 16:14

Where do you find that please SSK
Thanks

The Met charts I've checked don't say anything about the closed area being anywhere near the UK or German. And the chart only goes to Sunday.

lasernigel

14th May 2010, 16:45

Hope not due back from Koln on Tuesday morning!:\

Defruiter

14th May 2010, 17:36

Which charts? I don't see any for monday on the met office website...

EIPCW

14th May 2010, 20:50

Nor can I find any predictions for the beginning of the week, but I hear from a well placed insider whos says he heard from a reliable insider in an un-named UK based carrier that MON/TUE next week we may see the "black zone of doom" covering most of Northern UK and Irish airspace.

Comments please guys n gals?

aguadalte

14th May 2010, 21:20

Rhenish Institute for Environmental Research - EURAD-Project (http://www.eurad.uni-koeln.de/index_e.html)

lomapaseo

15th May 2010, 00:13

peter we

15th May 2010, 09:44

As well as a greater spread, the ash cloud is also reaching higher into the atmosphere – currently up to nine kilometres – which will continue to affect aviation. All domestic flights have been cancelled until further notice and there are delays and alterations to international flights.

Volcanic ash falls on Reykjavik, citizens fail to notice | IceNews - Daily News (http://www.icenews.is/index.php/2010/05/14/volcanic-ash-falls-on-reykjavik-citizens-fail-to-notice/)

The higher the cloud the further it seems to travel.

I don't know if it will affect UK/Ireland, based on this -

Metcheck.com - Atlantic Jet Stream Forecast - [Updated on 15 May 2010 at 10:00] - Weather Feeds - Live Data - Long Range Weather Forecasts (http://www.metcheck.com/V40/UK/FREE/jetstream.asp)

j4ckos mate

15th May 2010, 09:54

I have followed this thread from the first post on the first day, i have checked it every few hours because it effects my job, and also my holiday.
I have been planning shipments and jobs around the cloud checking the long term weather forecast, on all the twitter pages i can find,

so far this morning i have found 3 maps all showing different locations,

first one radar virtuel's overlay, second one the icelandic map which shows a small concentration, and the mapped.at one, all three maps claim to be upto date and all show different conficting information,

I have no technical knowledge whatsoever of aircraft engines, but i am fond of them the most when they are spinning round very fast and im sitting above one.

I do find it hard to believe though that in the last fifty years or so of jet engines somewhere on earth, there hasnt been a plane flying through a thick volcanic ash cloud at somepoint. most of java, is volcanic, and alaska,

currently according to radar virtuel there are 575 aircraft up and about, and i think yesterday there were 29,000 flights within the eurocontrol area.
My feelings are at first everyone panicked, it was all over the media, it was in the papers, all over the web, and i am inclined to think that we over reacted a little.

i reckon when the heat comes out of the election news, this will become front page news again and whip us all up into a frenzy,
the latest news on the caa website is 11 may, the lastest news on nats is last nigjht and there are no restrictions,

its almost like the recession, we seem to be almost taling ourselves into airspace bans,

martin102

15th May 2010, 10:24

BBC News reporting BA cancelling 1 flight to Edinburgh and 2 to Aberdeen. No link to story as yet.

BOAC

15th May 2010, 10:34

Looking at Peter's forecast jets I reckon SSK is right. This could emasculate the BA strike somewhat:)

MPN11

15th May 2010, 12:22

CLICKY-LINK (http://news.bbc.co.uk/1/hi/uk/8684540.stm)

BBC Breaking News - possible UK ash closures for 2 days from tomorrow.

Air.Farce.1

15th May 2010, 12:36

Met Office: Icelandic volcano - Ash concentration charts (http://www.metoffice.gov.uk/corporate/pressoffice/2010/volcano/ashconcentration/#D1)

MPN11

15th May 2010, 12:42

Oh this is fun ... NOT

Original flight last month cnx due to ash, re-booked flight for next week cnx due to strike, and now the re-re-booked flight may be cnx due to ash? :ugh:

Someone doesn't want me to reach the USA. :{

Redredrobin

15th May 2010, 16:43

There is now a five day forecast, with a caveat that it is not for operational use and heavily flagged that it assumes no change to volcanic output during the five day period, (though it seems to be OK for newspaper headlines):
Met Office: Five Day Volcanic Ash Charts (http://www.metoffice.gov.uk/corporate/pressoffice/2010/volcano/ashconcentration/fiveday.html)

ChristiaanJ

15th May 2010, 17:07

MPN11,

Try Walking Across.

soddim

15th May 2010, 17:21

It appears that Ryanair will now have to pay considerably more than just the ticket price to compensate stranded passengers:

BBC News - Italy fines Ryanair over volcano ash 'failings' (http://news.bbc.co.uk/1/hi/business/8684683.stm)

peter we

15th May 2010, 18:32

Ryanair was not immediately available for comment.

Funny that, I thought MOL would be happy at the free publicity. I'm not fan of his, but I don't think the regulations envisage such a situation. An ash risk supplements would be justifiable, in my opinion.

ILS25

15th May 2010, 21:31

Irish Aviation Authority website:

2030 hours local - Saturday 15th May 2010: Due to the prevailing weather conditions, and sustained low-level volcanic activity over the past number of days, the volcanic ash cloud is drifting towards Ireland from the North Atlantic. The cloud is likely to be over the west coast early tomorrow morning, and will cover the rest of the country later in the day.

Irish Aviation Authority - 2030 hours local - Saturday 15th May 2010: Donegal, Sligo and Ireland West (Knock) open until 0700 hours local, Sunday 16th May 2010. All other airports open until at least 1300 hours local. (http://www.iaa.ie/index.jsp?p=93&n=96&a=922)

ILS25

15th May 2010, 22:54

NATS:
Update on Saturday 15 May, 2345
A high density volcanic ash cloud is rapidly encroaching on Northern Ireland. As a result, a no-fly zone has been imposed by the CAA in airspace over parts of Northern Ireland, however Belfast International and Dublin airports will remain open, from 0100 (local) to 0700 on Sunday 16 May.

G-AWZK

15th May 2010, 23:14

Sky News are reporting that a BA memo says that BA have found no evidence at all of any damage due to the volcanic ash.

Is BA trying to make a political point? Could it be that the caution shown by the authorities has been justified?

david.craig

16th May 2010, 00:09

CO16 from Newark - Glasgow and 36 to Edinburgh cancelled tonight, by the looks of it just before scheduled departure.
Similarly, US468 to Glasgow, the first of the season cancelled

Walnut

16th May 2010, 11:00

Here we go again, another few days of massive disruption and cost to all.
This eruption could go on for a long time and with the Azores high soon to establish itself then the wind direction could be unfavorable for long periods.
I am aware that the ash levels permitted has been raised, but has any real research been done recently? IF it has then is it not possible for monitoring a/c be assigned to each airport, with the task to fly 20nm circles around the said airport. IF they were equiped with sensors then real ash levels could be detected.
At the moment the Met Office is providing forecasts based on computor models, just as they do for "proper weather". If these monitor a/c detected say a safe corridor to the SE of a particular a/p then at least we would not need these total shutdowns.

brooksjg

16th May 2010, 11:19

At the moment the Met Office is providing forecasts based on computor models

at the moment AND for the foresseable future!

Do you have any evidence at all that the tuned-up models currently in use are actually giving incorrect track and coverage data for the VA?

Or, alternatively, any evidence that 'safe corridors' actually could / have exist(ed) for useable periods of time, in conflict with data from the models.

(...thought not!)

radarman

16th May 2010, 11:27

We were 'Black' last Saturday night, but no sign of any ash on my balcony the next morning. However, every summer we regularly wake up to find everything covered in a thin film of rust-coloured dust- just like brown talcum powder. This is fine dust lifted from the Sahara, so presumably is sand/silica based, and therefore chemically not too far removed from volcanic ash. (I stand to be corrected). How is it that aircraft fly quite happily through this much heavier, and visible, dust concentration without any fuss?

crispey

16th May 2010, 11:29

Wetter : Wetterzentrale : Top Karten : Prognose - GFS Europa (http://www.wetterzentrale.de/topkarten/fsavneur.html)

Shows the upper winds moving from their current NW flow over Iceland towards UK to a SW flow fairly soon as the jet stream shifts.

MPN11

16th May 2010, 11:32

@ radarman ... apparently the chemical composition is significantly different, especially in respect of melting point. Much discussed somewhere on the previous 143 pages! ;)

donnlass

16th May 2010, 16:12

BBC News - Ash cloud 'could cause disruption in UK for 20 years' (http://news.bbc.co.uk/1/hi/uk/8685229.stm)

An aviation expert has warned that the ongoing problem with an ash cloud, drifting from a volcano in Iceland, could cause disruption 'for more than 20 years' - affecting the UK and the rest of the world.

Speaking to the BBC, David Learmount said that there is no technological way around the situation, with no possibility of engines being designed that can withstand damage caused by ash.

He warned that any aircraft attempting to fly through ash would have its engines permanently damaged, and would be destined for the scrapheap.

F14

16th May 2010, 16:18

20 years hahaa:ugh:

I think we run into a more safety related problem by taping up the ports and engines. Remember BirgenAir B757. And countless others over the years.

The damage done to the industry is very bad. We need drones flying off RN ships into the cloud to gather real data.

MrMachfivepointfive

16th May 2010, 16:20

The Pacific ring of fire is continuously active, as are Etna and Vesuvio. Still the world has not been shrouded in a unpenetrable volcanic ash clouds and the Pacific and Med seafloor are not littered with jet airliner wrecks. Even if Ejzkzjlzjyzjklz@klzjokul continues to belch, burp and fart for two years like it did last time, airlines and authorities will adapt and plan around it.

MPN11

16th May 2010, 16:27

The damage done to the industry is very bad. We need drones flying off RN ships into the cloud to gather real data.

Sadly the UK has neither the Navy, nor the drones, for that task ... nor indeed the sensors, or the data interpreters. Or the time, or the money. :uhoh:

Incidentally, the Navy is not established and funded to support Civil Aviation ... but I guess you knew that anyway :cool:

F14

16th May 2010, 16:34

But if you think about the money lost already from the airline business, surely our hi-tec "boffins" could rig something up to a predator? fly it off a flat top.

Walnut

16th May 2010, 17:18

"Brooksig" suggested that he had complete faith in the Met models.!!!
Why then do we dept from JFK to LHR with a fcast on limits and a suitable Alt, which on arrival has a Metar which makes the approach feasable. All I am suggesting that to canx flts on a computer ash model however accurate is daft. We need a method of actually finding the ash level at an airport on arrival, just as we find out the RVR or w/v at the airport just before making the approach.

MPN11

16th May 2010, 17:23

@ Walnut ... Nail/Head/Hit. Unfortunately, nobody has yet come up with a credible, wide-ranging, affordable detection system that will allow every airfield/airport in Europe to have the equivalent of a Metar.

In fact, there's almost no data gathering capability at all, especially when considering the 3-dimesional, multi-layered threat from ash.

The last few miles on final approach [related to landing minima] is different from having every airway, holding pattern, TMA and airfield accurately measured for ash at every intermediate level up to FL360.

brooksjg

16th May 2010, 17:45

"Brooksig" suggested that he had complete faith in the Met models.!!!
No I didn't!!!
In the absence of any alternative I just asked you for your evidence of inaccuracy, within the limits of the modelling as offered. I have absolutely no doubt that the models ARE less accurate than 'spot' measurements using a probe on an aircraft but erring on the side of safety.

As has been pointed out already, actual measurement of all the FLs and all areas surrounding any particular airport just cannot be done. For a start, you can't easily add extra (recce) aircraft to the traffic already there!

And, finally, what use would 'the equivalent of a METAR' be at the start of a 7 hour flight? Modelling should give a usable forecast of the VA situation on arrival at (eg.) LHR - actual measurements from 7 hours ago would be useless. The key problem is how often does the actual track of an ash cloud vary from the prediction: in other words, how often is the short-term weather forecast incorrect? You can see an example of the model being 're-trimmed' during today for 0600 tomorrow: the southern boundary is now further south than predicted 8 hours ago.

In practice, what improvement of accuracy / sensitivity could be achieved or is needed?

IcePack

16th May 2010, 19:23

Last time one of these Icelandic things went pop, I can't remember the airspace being closed, so what's changed. Also Anyway Catania is usually covered in ash, so can we still go there. I'm with the this does not make sense brigade.:confused:

fireflybob

16th May 2010, 19:50

Branson: new restrictions 'a joke' (http://news.aol.co.uk/branson-new-restrictions-a-joke/article/20100516074531152231189)

takoon

16th May 2010, 19:54

Hmmmm okay, so what do make of the two research planes finding a 'distinct' layer today ?

"Two dedicated atmospheric research aircraft, one from the UK and another from Germany, flew on Sunday to investigate the volcanic ash plume moving over the UK. Both aircraft found an extensive area of ash generally between 15,000ft and 20,000ft covering central and northern UK, drifting south. In many areas the cloud was clearly visible to the naked eye and was described as ‘a grey-black layer’. The pilots of the DLR aircraft reported that ‘one should not fly into this layer’."

This is the quote from the met office site, is the bearded wierdie advocating flying through the middle of that then :ugh:

Sunfish

16th May 2010, 19:58

Richard baby, do you think that the restrictions are in place just for fun?

Thunderbirdsix

16th May 2010, 20:11

Irish Aviation Authority ran two flights looking for ash today, one went South and the othe Went North and West, the North flight encountered ash visible to the naked eye and was describied as bad in places, special filters on the aircraft had ash in them when the plane landed. The other flight found nothing.

Mr @ Spotty M

16th May 2010, 20:18

I think the problem maybe that the no fly zone is because the ash cloud was forecast outside of the new limits between 0 and 20000 ft. The test a/c seem to show the forecast is incorrect and that it might be safe to fly below 15000 ft, say up to 10000 ft, thus keeping the airports open.

BOAC

16th May 2010, 20:20

Last time one of these Icelandic things went pop, I can't remember the airspace being closed, so what's changed. - if you mean 2004, it did not go so high and drifted to the east south east. We 'bent' south of it from KEF to CPH for a day or so and eventually rain brought most of it down over the oggin.

brooksjg

16th May 2010, 20:37

an extensive area of ash generally between 15,000ft and 20,000ft is mentioned in the latest report but as far as I can see the word 'distinct' (as in 'distinct layer') does not occur. This phrase DID get used in a previous flight report from 5th May. Who can say exactly how a VA cloud will move, EXCEPT based on precisely the atmospheric modelling already being done. OK - the vertical component looks like it might be made more specific with more work - but I don't know what's going on in that part of the forest. Other people around here might....?

The extent to which VA forms 'distinct' layers only a few thousand feet thick, or more diffuse layers covering 'generally' FL150 to FL200 is a bit academic anyway. For practical purposes, any VA between ground level and FL200 in (say) a 50 mile radius around an airport should be suffiicient to close it. ATC cannot realisitically factor-in the presence of VA in a particular set of levels and small area(s ) when directing traffic. How could that possibly work in practice. The resolution of the cloud model predictions looks to me pretty much as small as you're likely to get, combined with safe margins of error, in flying and control, AND coping with unexpected manoeuvres caused by an aircraft suddenly appearing in the wrong bit of sky!

Desk-pilot

16th May 2010, 21:13

It's quite simple really, the Met-office are the experts in forecasting both weather and ash. The CAA are responsible for identifying the no-fly zones. Just cos weird beard, BA and a bunch of airline accountants don't like it, that doesn't make the experts wrong.

What the airlines need to do is get a hell of a lot better at acting on the information IN ADVANCE to avoid passengers waiting for hours at airports needlessly. The met-office forecast this ash cloud hitting us a couple of days ago, the research aircraft have validated their projections today. There really is no excuse for the airlines allowing their pax to turn up for flights that any idiot could tell 24 hours in advance weren't going to run. They seriously need to get their finger out and stop messing their customers about like this.

If you believe the charts this evening it looks like airports like SOU, BOH etc are out for tomorrow, so why can't the airline ops people save people the trouble of turning up and waiting around for flights that almost certainly aren't gonna go...

Head in the sand and dodo spring to mind I'm afraid. Passengers understand that the ash cloud isn't the airline's fault - what is their fault is not being up front about what is going on and that is only going to make the passengers more annoyed.. Nobody wants to waste a day hanging round an airport - better to reschedule and fly another day.

Desk-pilot

baopsman

16th May 2010, 21:54

You'll find most if not all, airlines will tend to wait for the NOTAM shutting airfields/airspace to be issued before pulling the plug on any operation. Unfortunately NATS don't play to the same lead-time as most airlines and trying to "do the decent thing" by giving passengers early notice before a NOTAM is issued has back-fired recently. I refer to the last closing of Scotland a few weeks ago, airlines cancelled late the day before only to find out when the NOTAM was issued it was only the west coast ie, GLA/PIK that was affected.

ribt4t

16th May 2010, 22:07

United seems to be canceling tonights flights into London.

spider_man

16th May 2010, 22:12

Gatwick and Heathrow closed from 1am.

ExSimGuy

16th May 2010, 22:21

Just been bumped from GF007 BAH-LHR, "Due WX", so I guess LHR has been closed, or is expected to be before 06:00 tomorrow.

Anyone know what the preditions are? Could it clear in the next couple of hours? Or should the pax be demanding hotac? Last time I had a GF delay, the @delay@ (tech aircraft) went on until 05:00 from a ETD of 01:00, and then by the time they got us into hotels it was only an hour before getting back on the bus for the next flight went out so hardly worth it :confused:

Diversification

16th May 2010, 22:27

The following is taken from "Teknisk Ukeblad" which is a jounal published by the Norwegian polytechnic society in Oslo.

"Satellite Images

The ashes that spread from the volcanic eruption is powdered stone that comes in and blocks the ventilation of the engine, but the plane's radar can not detect it. At NILU, with the researcher Fred Prata at the helm, has been developed a set of algorithms that convert data from U.S. satellites which could be useful for the aviation industry.

Prata uses publicly available images taken with an infrared camera by NASA satellites, then runs it through his proprietary modeling program. There are calculated the total ash quantity, concentration and size of particles in the discharge.

- Fred has several patents on this, and we have also taken this technology a step further and use it against other commercial applications, including to measure emissions from ships, "he said."

Apparently a special version of the IR camera and its software is being developed for use as a warning device on commercial aircraft. - similar to weather radar.

Finally for those of you who do not believe, there is a rather large amount of data available about single or double engine shutdown incidents at high altitude. Most of this is assumed be due to ice particles, but some may also on ash or mixed ice/ash particles.

Havana

16th May 2010, 22:31

The BBC news seems to indicate a minimal closure of LGW and LHR. Hopefully opening before midday (London time)

H

F14

16th May 2010, 22:31

last week I saw Volcanic Ash in clouds, over the English Channel and down in Spain, north of Madrid. The clouds are dirty looking, but very thin, maybe 100-200 feet in depth. Like smoke from a fire on a still day.

This is the biggest scam ever and I hope it gets sorted using technology, before an airline folds up under the financial pressure.

Airclues

16th May 2010, 22:50

ExSimGuy

The BAA website is saying that LHR is closed between 0100 and 0700 tomorrow (Monday).

Dave

ExSimGuy

16th May 2010, 23:21

Thanks Dave, so our latest "ETD" of 03:30 could be realiastic, rather than hopeful!

lomapaseo

17th May 2010, 02:26

Diversification

Finally for those of you who do not believe, there is a rather large amount of data available about single or double engine shutdown incidents at high altitude. Most of this is assumed be due to ice particles, but some may also on ash or mixed ice/ash particles.

Where does this extrapolation fit into the discussion subject:confused:

It's already known what ice crystals can do on their own and where they are likely to be encountered so as to avoid.

Likewise it's already known what certain types of encounters with VA can do and how best to avoid and/or cope with it.

The two are not the same as far as the engine is concerned nor have they ever been linked together.

Walnut

17th May 2010, 04:49

BBC now saying LHR & LGW will have a limited operation from 0600Z, any further info?

Charley B

17th May 2010, 05:09

LGW Atis( 5 mins ago) is saying departures only from 06.00 on 08R--wondered why it was so quiet!
Hopefully ash will disappear soon!
0727
Still the same here (as apparently ash cloud is to the west of the airport) all Spanish etc deps will be going out off 8R on a DOVER/Clacton dep
Ist departure is imminent:)

Nemrytter

17th May 2010, 05:46

Hello JetII

Airbubba

17th May 2010, 06:02

LGW Atis is saying departures only from 06.00 on 08R here (that was 5 mins ago)--wondered why it was so quiet!
Hopefully ash will disappear soon!

Looks like BA 64 is the leader of the pack into LHR as the arrivals start again with a thundering heard in hot pursuit in the holding patterns...

brooksjg

17th May 2010, 08:52

One factor in your favour - apparently still 'scheduled'
But two potentially against:
- The southern edge of a Black ash area is predicted to move Eastwards, VERY close to LGW between now and 1200.
- There are no arrivals into LGW at the moment, so if the aircraft in question is not already there, the Boss ain't moving, until 1800 at earliest. :uhoh:

Cameronian

17th May 2010, 09:08

Thank you, booksjg - I'm guessing you are addressing me.... It appears that the mods have deleted my query and Charley B´s reply.

Bertie Thruster

17th May 2010, 10:54

Curiously the latest midday ash notam now shows no sign of the no fly black zone that was over England this morning! (Wonder what will happen to the VAAC graphics at midday?)

itsresidualmate

17th May 2010, 11:03

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.

MPN11

17th May 2010, 11:03

Live on BBC ... all restrictions at LGW and LHR have been lifted.

sabenaboy

17th May 2010, 11:13

Live on BBC ... all restrictions at LGW and LHR have been lifted.

Very strange. I would have thought they'd have to keep it closed.

http://www.metoffice.gov.uk/corporate/pressoffice/2010/volcano/ash_concentration_images/auto-zoom-FL000-200-201005170600-201005171200.gif

green granite

17th May 2010, 11:20

Quite a few flights overhead here in North Beds at about 10 to 15K, thought it was strange having looked at the Met office charts earlier. :confused:

Perrin

17th May 2010, 11:34

I know this is a pilots forums but being a retired engineer after looking after you lot for 40 some years I feel I can ask a question on this forum.
Why is Ryanair always first to cancel so many flights out of Prestwick and other airports?

Take care out there, :confused: Peter

MPN11

17th May 2010, 11:34

The Beeb was suggesting that wind had swung to the SW earlier than expected.

RoyHudd

17th May 2010, 11:53

Those scary charts are 6-hourly PREDICTIONS, not actuals. Man cannot live by predictions alone.:)

itwasme

17th May 2010, 12:32

Latest chart just issued:

http://www.metoffice.gov.uk/corporate/pressoffice/2010/volcano/ash_concentration_images/auto-zoom-FL000-200-201005171200-201005171200.gif

sabenaboy

17th May 2010, 12:33

The latest charts look like this. Strange that predictions change so quickly. Or would there be someting else going on?

Bertie Thruster

17th May 2010, 12:44

If you look closely at the 0600 chart, in post 2883, you can see the lower black zone is a coffee stain from the forecasters mug.

MPN11

17th May 2010, 12:51

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 :cool:

SLFguy

17th May 2010, 13:00

What have you started - I can see a wild boar rearing up out of Europe.

I guess you also saw a bore.

brooksjg

17th May 2010, 13:06

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!). :confused::}

IB4138

17th May 2010, 13:11

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?

brooksjg

17th May 2010, 13:15

But previous research flights took place on Saturday (??) which (presumably) confirmed what was being forecast then! Very odd

Facelookbovvered

17th May 2010, 13:19

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.

B-HKD

17th May 2010, 13:29

The computer simulations their are creating suck because they are using PC's and not Mac's :E

Just wondering

17th May 2010, 13:43

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

peter we

17th May 2010, 13:48

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?

Pressure to justify re-opening the airports requires the charts to be redrawn.

I'd guess. We have a new government after all.

brooksjg

17th May 2010, 13:50

....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!

befree

17th May 2010, 14:00

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.

GarageYears

17th May 2010, 14:07

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

ILS27LEFT

17th May 2010, 15:50

Well said, in fact this webcam
Katla | Ríkisútvarpið vefur (http://www.ruv.is/katla/)
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. :ok: :ok: :ok:

VeeAny

17th May 2010, 17:14

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.

peter we

17th May 2010, 18:05

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."
Ryanair demands more lenient ash-protection rules (http://www.flightglobal.com/articles/2010/05/17/342066/ryanair-demands-more-lenient-ash-protection-rules.html)

Ryanair noticed it. Either the danger or the precaution is fiction....

oceancrosser

17th May 2010, 18:12

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.

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.

plane speak

17th May 2010, 18:30

The CAA change the rules again.....press release:

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. Link here (http://www.caa.co.uk/application.aspx?catid=14&pagetype=65&appid=7&newstype=n&mode=detail&nid=1881)

topper3

17th May 2010, 18:40

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

slf99

17th May 2010, 19:34

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

17th May 2010, 20:23

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

17th May 2010, 21:04

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

17th May 2010, 21:34

Better to be safe than sorry, huh?

SEVIRI BTD (http://brunnur.vedur.is/pub/bolli/btd/)

Ends at the current day ^

petitb

17th May 2010, 22:12

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

18th May 2010, 06:36

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

18th May 2010, 07:05

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

18th May 2010, 07:10

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

18th May 2010, 07:16

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 :ugh:

All sounds very scientific

Pace

brooksjg

18th May 2010, 07:24

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

18th May 2010, 07:34

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

18th May 2010, 07:57

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/aircraft/bomber/north-american-b-25-mitchell/north-american-b-25-mitchell-mt-vesuvius-01.png

sabenaboy

18th May 2010, 08:29

@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:ugh: )

Best regards,
Sabenaboy

infrequentflyer789

18th May 2010, 09:42

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 (http://www.dailymail.co.uk/news/article-1279221/The-ash-cloud-Inaccurate-Met-Office-forecast-causes-airport-chaos-50-000.html)

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

18th May 2010, 09:54

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

XC-99 (http://en.wikipedia.org/wiki/Convair_XC-99)

Slow but safe? ;)

green granite

18th May 2010, 11:30

Mir

18th May 2010, 12:29

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

18th May 2010, 13:16

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

18th May 2010, 13:49

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!

Trig71

18th May 2010, 15:19

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!

g m c

18th May 2010, 15:44

DUFFUS

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

atlast

18th May 2010, 15:49

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!

BOAC

18th May 2010, 15:52

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..

JanetFlight

18th May 2010, 16:25

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

brooksjg

18th May 2010, 16:30

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!

sky9

18th May 2010, 17:31

Gengis,

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

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.

lomapaseo

18th May 2010, 17:58

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

Data is like that

Pace

18th May 2010, 20:55

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

BDiONU

18th May 2010, 21:06

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

ChristiaanJ

18th May 2010, 21:12

Then that beggars the question isnt the pilot better placed with his/her experience on determining what is safe or not...
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

dublindispatch

18th May 2010, 21:17

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?

Pony Poo

18th May 2010, 21:24

no need to SHOUT!

ChristiaanJ

18th May 2010, 22:01

Also anyone know if the engine people are going up the Iceland, taking a plane load is ash off the ground....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

ChristiaanJ

18th May 2010, 23:42

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

BOAC

19th May 2010, 08:06

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

PBL

19th May 2010, 08:47

I blogged on this topic a couple of times over the last month. People might be interested in http://www.abnormaldistribution.org/2010/04/20/flying-in-volcanic-ash/ , http://www.abnormaldistribution.org/2010/04/22/flying-in-volcanic-ash-part-2/ and http://www.abnormaldistribution.org/2010/04/28/the-political-economy-of-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

forget

19th May 2010, 09:10

Two minutes on Google, from another site. :hmm:

These pictures and the engine damage are NOT DUE TO VOLCANIC ASH !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I know for a fact that the engine damage is NOT from a volcanic ash event. It is an engine diffuser failure. I work for Cessna and have this fact confirmed by Customer Service, Cessna Engineering Propulsion. This is a hoax that has been spreading on the internet. I have seen these photos a couple of weeks ago and have confirmed that it is NOT DUE TO VOLCANIC ASH.

CEN10RA135 (http://www.ntsb.gov/ntsb/brief2.asp?ev_id=20100302X25146&ntsbno=CEN10RA135&akey=1)

Pictures here.

Engine Damage Photos Misunderstood As Ash Damage — Civil Aviation Forum | Airliners.net (http://www.airliners.net/aviation-forums/general_aviation/read.main/4813957)

Pace

19th May 2010, 09:38

PBL

This is the sort of mindless, plain ignorant hyping that has caused us to be where we are today at vast cost to our industry.

Do you believe anything you are told or see at face value without questioning it ?
As a professional researcher you should know better!

Pace

Low Flier

19th May 2010, 10:01

http://i.telegraph.co.uk/telegraph/multimedia/archive/01639/mattb19052010_1639493a.gif

PBL

19th May 2010, 10:35

Thank you, forget, I am aware of the rumors, but want to know if anyone has a provenance

PBL

Lomon

19th May 2010, 11:34

GarageYears

19th May 2010, 11:53

Now that airlines are allowed to fly through some of the ash clouds providing the engine manufacturer has certified their engines are up to the task, where will the liability lie if there is (perish the thought) an incident?First question - how would anyone prove the ash concentration that caused such an incident was above or below whatever (arbitrary) level was stated to be safe. Not being flippant but the evidence has a tendency to blow away.... i.e. the ash cloud itself.

- GY

Pace

19th May 2010, 12:27

Lomon

That is a tricky one! Where does the liability lie if damage is sustained flying through hailstones in a known area of thunderstorm activity which we operate through on a regular basis.

Where does liability lie with Bird ingestion through known migration paths or at sea based airports?

What is the difference other than the two above have caused loss of life and known engine damage while to date there has been no loss of life caused by Ash in even dense encounters in over 50 years of aviation.

There is far more risk to crashing on landing and takeoff and loosing your life within acceptable wind and shear limits than ever being killed by an ash encounter. Maybe we should call for zero wind for takeoff and landing in the next safety based campaign :ugh:

Pace

lomapaseo

19th May 2010, 12:32

Pictures here.

Engine Damage Photos Misunderstood As Ash Damage — Civil Aviation Forum | Airliners.net

A lot of what is seen here is the after effects of leaving an engine run-on for minutes after experiencing an uncontained failure. Probably the pilots were in a high workload regime.

(engines don't often snuff out all the flame but they do run out of air in the combustor, but not fuel, until they are shutdown following a major failure.)

BOAC

19th May 2010, 12:48

Well, whatever.It looks from the synoptics as if the UK is OK until 23rd at least.

infrequentflyer789

19th May 2010, 13:01

Playing Devils advocate

Now that airlines are allowed to fly through some of the ash clouds providing the engine manufacturer has certified their engines are up to the task, where will the liability lie if there is (perish the thought) an incident?

The engine manufacturer for stating their engines can cope in the ash?
The airline for taking the engine manufacturers word?
The regulator for accepting the idea?

Hmmm the lawyers must be rubbing their hands in glee and anticipation!

Liability will lie whereever the lawyers get the courts to decide it does - as per usual. If I was an ambulance chaser of this type, I'd be far more excited about pitot tubes, and birds.

Where does the liability lie in those cases ? The aircraft / component mfr. who designed to the (inadequate) tests ?
The regulators who set the tests ?
The airlines who carried on flying, based on the certification, after previous incidents showed inadequacies ?
Surely if you look at the list of previous pitot incidents almost all with one type of probe, it was obvious they weren't good enough... and clearly a bird ingestion standard based on only one 4lb bird is totally inadequate for flying near flocks of geese. Obviously (if you are an ambulance chaser) someone should have spotted those issues and taken action before people died. Who ? Whoever has the money (or just sue them all).

VA, on the other hand, hasn't managed to down an aircraft yet. A few broken, or prematurely worn, engines will be sorted out between the airlines and the mfrs. There's probably more money in hitting the poor delayed punters with "sue for a refund" scams.

sabenaboy

19th May 2010, 14:03

First: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?

And then, after someone exposed it as a hoax...Thank you, forget, I am aware of the rumors, but want to know if anyone has a provenance

Yeah sure! :ok:

:}:}:}

Sunfish

19th May 2010, 21:06

Garage Years:

First question - how would anyone prove the ash concentration that caused such an incident was above or below whatever (arbitrary) level was stated to be safe. Not being flippant but the evidence has a tendency to blow away.... i.e. the ash cloud itself.

Very, very simple. Erosion and overheat damage to turbine blades and nozzle guide vanes associated with glass clogged cooling holes.

By the way, the diffusion of responsibility between engine/airframe/ Met office/airline/insurer/crew and regulator in the event of a series of extremely costly Ash damage incidents is exactly what has kept you grounded until enough research and negotiation could be done to understand and manage the risks.

Pace

19th May 2010, 21:29

Very, very simple. Erosion and overheat damage to turbine blades and nozzle guide vanes associated with glass clogged cooling holes. Very simple really.

Sunfish

Sorry cannot agree with you that its simple really ;) You could quite easely have an area marked as below the accepted limits in Ash and have one cloud which is unique and solitary but of a much denser level than the remaining area.

Nothing is constant sadly in our atmosphere.

I can well remember flying a twin to Malaga single pilot with only the owner on board airways at FL120 Near Madrid. Radar gave me help with storm cloud avoidance as did my on board radar. I picked a way between two cells in VMC. The ground temperature was 42 deg C.

As I passed well clear and between the cells I experienced something I had never done in 20+ plus years. The IAS shot from 160 kts IAS to 65 kts IAS in seconds and the aircraft felt as it had flown into a vacuum. No control response, No Pitch response, No increase of speed with power.

The aircraft sank vertically like a towerblock lift for 2000 feet as if in a vacuum and then came alive again.

You simply cannot prove anything in the atmosphere as being constant! ash density or otherwise especially with computer predicted movement. One area may be ok while a few hundred metres and its not.

The best indicator with storms or otherwise is to use your eyes and your instincts and knowledge as relying on aids only whether aircraft based or land based will give you a shock you dont want.

That is why I dont hold with the science but do with pilots and good old see and avoid.The SCIENCE is an aid to the captain not the CAPTAIN and for me thats the whole basis of my arguement with this thread. Listen to the airlines and the pilots and thankfully that message seems to be proving correct.

The same goes with ASH which to date has not harmed anyone in I repeat over 50 years when there were no fancy gizmos to mislead anyone which sadly also now seems proved to be a costly mistake.

Pace

sky9

19th May 2010, 22:08

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.

Glass is made by heating silicon dioxide, otherwise know as sand.

ChristiaanJ

19th May 2010, 22:53

Glass is made by heating silicon dioxide, otherwise know as sand.Not quite.....
Glass is made by mixing silicon dioxide (sand) with various other chemical substances and heating it.
The result is a somewhat odd material, neither liquid nor entirely a solid, but with a melting pointing considerably below pure silicon dioxyde.
Hence the problem...

CJ

Sunfish

20th May 2010, 03:00

Pace:

Sorry cannot agree with you that its simple really You could quite easely have an area marked as below the accepted limits in Ash and have one cloud which is unique and solitary but of a much denser level than the remaining area.

Nothing is constant sadly in our atmosphere.

I can well remember flying a twin to Malaga single pilot ................

...............The best indicator with storms or otherwise is to use your eyes and your instincts and knowledge as relying on aids only whether aircraft based or land based will give you a shock you dont want.

That is why I dont hold with the science but do with pilots and good old see and avoid.The SCIENCE is an aid to the captain not the CAPTAIN and for me thats the whole basis of my arguement with this thread. Listen to the airlines and the pilots and thankfully that message seems to be proving correct.

The same goes with ASH which to date has not harmed anyone in I repeat over 50 years when there were no fancy gizmos to mislead anyone which sadly also now seems proved to be a costly mistake.

I'm afraid you just don't get it.

1. See and avoid doesn't work by day with fine ash clouds as has already been demonstrated. It certainly doesn't work at night.

2. With at least 1000 flights per day to and from Europe, we are talking about the balance of probabilities of finding ash. It is irrelevant if one aircraft or ninety aircraft make it through without ash damage. Your personal experience is irrelevant.

This is about managing risk for a fleet of 1000+ aircraft engaged in European travel at any given time. As I said many pages ago, the penalty for getting the ash forecasts wrong is hundreds and hundreds of damaged aircraft sitting on the ground for months as they wait for their engines to be rebuilt by overloaded maintenance facilities staffed by exhausted engineers.

To put it another way, there are not hundreds of spare engines sitting around in Europe or America for some mass engine change.

To put it yet another way, suppose the forecasters get it wrong, or the volcano decides not to cooperate and Forty B747's need engines changes as a result. Are you going to sit there and argue that Boeing/GE/RR or the airlines should have had 160 spare engines just sitting around unallocated against this possibility? I can tell you they don't.

There are relatively few spares around against birdstrikes etc. The engines are monitored on the wings and then scheduled to be removed (sometimes as modules) during heavy maintenance and from there scheduled into engine overhaul and from there scheduled either to sit as a spare for a while or back onto another aircraft. The idea with that is to ensure that engine "Life" is managed so that engine changes due to time expired components don't happen except at scheduled heavy maintenance. Spares (blades and vanes) are usually ordered as sets, or overhauled as sets to fit in with the engine maintenance schedule.

It is a complex process and if you throw in anything other than the ordinary level of unforeseen engine changes, you will quickly run out of serviceable engines in the resulting chaos as well as suffer massive cost overruns.

jonwilly

20th May 2010, 04:12

Engine Damage Photos Misunderstood As Ash Damage — Civil Aviation Forum | Airliners.net (http://www.airliners.net/aviation-forums/general_aviation/read.main/4813957/)

A friend forwarded to me, I would like comments from engineers more knowledgeable that I.

john

itsresidualmate

20th May 2010, 05:24

Mate, someone's driven a tank down that intake, it has absolutely 100% got nothing to do with ash! To my knowledge, nobody has found any ash damage in a commercial aircraft these past few weeks

Sunfish

20th May 2010, 05:34

If you read the comments at that URL you will see that this is NOT ash damage at all, but some sort of disk failure.

PBL

20th May 2010, 08:06

Aren't Internet forums wonderful?

I posted a question yesterday about a set of purported pictures of ash damage: Does anyone have a provenance for those pictures?

These are the same pictures to which jonwilly referred earlier today. The answer appears to be no, no one knows where they came from.

Let me pose the same question again today: does anyone have a provenance?

I found it particularly amusing that two people, Pace and sabenaboy, suggested I was being gullible, presumably on the basis of what they read on other anonymous forums on the Internet. Folks, maybe it is time to look up the meaning of "gullible"?

From what I understand of the physics and chemistry of ash damage to engines (and it is not much, but it is more than many here seem to understand), it is quite possible for an engine to shed a blade or three if affected parts overheat and the engine isn't shut down. And what you then look at is a broke engine, much as these pictures show.

PBL

Pace

20th May 2010, 08:39

I found it particularly amusing that two people, Pace and sabenaboy, suggested I was being gullible, presumably on the basis of what they read on other anonymous forums on the Internet.

PBL

Dont you also think its amusing That both SabenaBoy and myself actually fly jets albeit SabenaBoy flies larger jets than I do? ;)

The majority of ATPs I know appear to come from the same mould on views of this whole charade which has cost the industry a fortune and charade it is.

Thankfully as I dont want to see our already struggling industry brought to its knees by unfounded media hype and scaremongering some of us have tried to balance that aspect with a bit of sense.

You refer to yourself as a researcher yet appear to only add to unfounded scaremongering by desperately jumping at anything which may add to your cause.
Normally a researcher researches until they get facts which they then put out to the media.

You though plant a link to a picture with comments that if true it may convert the sceptics to your way of thinking.

Thankfully the pilots and airlines way of thinking is proving to be correct.

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

Your comments!

suggested I was being gullible, presumably on the basis of what they read on other anonymous forums on the Internet

This is the only forum I frequent as I already spend too much time with this one but that comment says a lot about you and other forums :(

Pace

sabenaboy

20th May 2010, 13:07

1. See and avoid doesn't work by day with fine ash clouds as has already been demonstrated. It certainly doesn't work at night.

Nope, Sunfish, at night "see and avoid" doesn't seem to work but, correct me if I'm wrong, until now there has never been an ash incident or damage while staying in daylight VMC.

This is about managing risk for a fleet of 1000+ aircraft engaged in European travel at any given time. As I said many pages ago, the penalty for getting the ash forecasts wrong is hundreds and hundreds of damaged aircraft sitting on the ground for months as they wait for their engines to be rebuilt by overloaded maintenance facilities staffed by exhausted engineers.

To put it another way, there are not hundreds of spare engines sitting around in Europe or America for some mass engine change.

To put it yet another way, suppose the forecasters get it wrong, or the volcano decides not to cooperate and Forty B747's need engines changes as a result. Are you going to sit there and argue that Boeing/GE/RR or the airlines should have had 160 spare engines just sitting around unallocated against this possibility? I can tell you they don't.

Oh come on, Sunfish, not again! :ugh:
Remember my question from post 2646 (http://www.pprune.org/rumours-news/412103-ash-clouds-threaten-air-traffic-post5678338.html#post5678338): "Sunfish, could you enlighten us please and give us ONE example of an aircraft that had extremely costly damage to the engine, after flying through an ash cloud so thin that it wasn't noticeable to the eye! Juste ONE example! PLEASE...!!!" Still awaiting an answer!!

Nothing catastrophic is going to happen if you fly through ash concentrations so low that it stays invisible to the eye. Maybe -with emphasis on maybe- there could be an increase in maintenance cost and for extra engine checks, but these costs will surely be much less then grounding thousands of airliners without a very good reason.

And pardon me for saying so, but looking at your profile and the a/c you're type-rated on, you're not really in a position where you can call yourself an expert. I think you will be in more danger by forgetting the carb heat on your Rotax (http://www.pprune.org/dg-p-general-aviation-questions/415427-thank-you-ymmb-tower.html), then you will be by volcanic ash in an airliner! Please don't forget what the "Pp" stands for in Pprune!

Ok, the above sentence is a cheap shot, and something I don't usually do, but the way you have been hanging on to your "oh boy, we're gone crash"-scenarios without valid arguments are getting very boring.

Best regards,
Sabenaboy

peter we

20th May 2010, 16:27

Pace and sabenaboy

So, both of you are pilots, in what way does that qualify you to make judgement on the engineering aspects of volcanic ash damage? I am not Jet engine engineer, but I will defer to the better knowledge of the manufacturers who disagree with your opinions. You are both obviously quite wrong and its a little disturbing that you think that you know better than the experts simply because you hold an unrelated qualification.

itsresidualmate

20th May 2010, 17:09

Peter, I am a jet engine engineer and as I've said before, none of us can find any evidence of damage. Any other engineers out there found any damage?

As far as I'm aware, ash has never caused the loss of one airliner. Birds on the other hand bring them down a fair bit. But we don't stop flying because a weatherman saw a couple of ducks in the air.

These ash regulations will make European aviation the safest in the world; because if they carry on there won't be an aviation industry left in Europe.

sabenaboy

20th May 2010, 17:23

So, both of you are pilots, in what way does that qualify you to make judgement on the engineering aspects of volcanic ash damage?

Peter We,

Allow me to refer to Pace's post 2642 (http://www.pprune.org/rumours-news/412103-ash-clouds-threaten-air-traffic-post5678135.html#post5678135). He already answered your question!

Regards,
Sabenaboy

peter we

20th May 2010, 17:31

As far as I'm aware, ash has never caused the loss of one airliner. Birds on the other hand bring them down a fair bit. But we don't stop flying because a weatherman saw a couple of ducks in the air.

If there is no problem than it won't be too difficult to persuade the manufacturers to loosen their guidelines then, will it?

I have no problem with solid evidence based decisions, but referring to the situation as a farce and blaming the 'authorities' for what is fundamentally the airlines own rules is ridiculous.

3rd_ear

20th May 2010, 17:44

Of some interest, the source of these woes up close. Quite impressive:

BBC News - Up close on Iceland's Eyjafjallajokull volcano (http://news.bbc.co.uk/1/hi/world/europe/8695652.stm)

itsresidualmate

20th May 2010, 18:06

If there is no problem than it won't be too difficult to persuade the manufacturers to loosen their guidelines then, will it?

:} lol, that's a good one! The old 'lightning response' of the aviation regulatory authorities and manufacturers!!!

I don't think this is about safety anymore, this is about ass covering. The manufacturers and authorities aren't losing money, so why should they rush to stick their necks on the line when there's a tinest chance they might get a lawsuit thrown at them?! Why not wait for a year or so, see if anyone does find any damage? I still believe that birds hold a far greater risk to commercial aviation than dispersed volcanic ash.

BDiONU

20th May 2010, 18:10

I don't think this is about safety anymore, this is about ass covering. The manufacturers and authorities aren't losing money,
Of course 'the authorities' are losing money, no flying = no revenue. My company loses circa £2million a day if there are no flights.

BD

itsresidualmate

20th May 2010, 18:12

Fair point BDiONU

Pace

20th May 2010, 19:13

If there is no problem than it won't be too difficult to persuade the manufacturers to loosen their guidelines then, will it?

Peter

The answer to that is Yes it would be difficult to make them move from what they have to anything which makes them more liable but unoffically NO!

Why should they? would you in their position? as prob they dont know either.

Pace

jshg

20th May 2010, 19:17

The tech log entries I have seen refer to 'unknown contaminant on turbine blades' etc etc. After assorted checks, the CRS states 'within limits' or similar.
But this 'unknown contaminant' could be almost anything - pollution, quarrying near the airport to name but two - and could have nothing whatsoever to do with the unpronounceable volcano. I am also told that there is (was) no baseline sample from the volcano, and until that happens the contaminant cannot be linked with the volcano.
In other words, if all engines had been subject to the microscopic internal scrutiny that they are now, 'unknown contaminants' could well have been found before the volcano, and could have been irrelevant.
Aside from the full strength Eric Moody volcano encounter, the major problem is surely going to be erosion and performance degradation - and that won't be apparent until engines are prematurely removed in the next few months. Our Lords and Masters are most likely barking up the wrong tree (imagine my surprise).

falconer1

20th May 2010, 21:29

if there had not been a total flight ban over Europe on that first w-end when the eruption had started in April we definitely would have seen some maybe even serious events on the civil side of aviation..

just want to remind everyone on what had happened to the Finnish F/A-18s..on that first w-end

That is a fact

What happens now, if I look through the new UK CAA procedures with TLZs etc etc , and we are talking of up to 4000 MG / m3, the folks from the engine manufacturers to whom I talked yesterday are just laughing..

Now, as an AOC holder you will have to "build a safety case"...

Just to say, they others also fly will not suffice..

And you as an operator will have to get the nod from the engine folks..

well, they will give you some maintenance and inspection requirements, maybe..( some of those could amount to nothing less, than having to perform a hot-section inspection every couple hundred hours on certain types..( which may make flying cost-wise unfeasible...it will destroy the bizplan of a lot of airlines..)

What I really want to know though, the engine manufacturers definitely will put a legal disclaimer on EVERY PAGE of their enhanced procedures, that in fact they DO NOT RECOMMEND flying in that cra...

So how do you build a safety analysis, if the most important link in the chain , the engine folks, will say, better dont do it..??!!

Dont get me wrong, I do understand that especially the UK is in trouble now, if that mountain continues on and on, depending on weather you in the UK will have high ash concentration days every week or every second week or so..

And I understand that keeping the planes up in the air beats reverting back to sheep farming and whiskey..( now that the EU even wants to "regulate" your hedge funds, and London could lose quite a bit of funky /junky biz)

and then on top your airspace gets dirtied up every 10 days..

I understand..

what I do not understand though is, up to now, we in aviation strived to have the best safety record and try to better it every decade or so..

If that new "let's all fly in the dirt now" should go fundamentally wrong, all the good work of the last decades to make commercial aviation one of the safest form of transportation in history, at least in North America and Europa,( am not talking about Africa, Russia etc etc) but all that could literally go up in smoke overnight...and you wont find any passengers no more even once that mountain will have stopped smoking..

And until now, for testflying you got paid....the traveling public though is paying for their seats in the back and at the end paying the salaries of all those wise-guy pilots here, who think it is a swell idea to suddenly cut back in safety..

think about it..

itsresidualmate

20th May 2010, 22:15

Falconer1

Remind me, how many F18s did the Finns lose that weekend? Were the crews able to eject before their jets smacked into the sea? Did they lose any SAR helicopters on the rescue mission? No?!

Might as well stick my head above the parapet!;
I don't believe there is a flight safety issue here. I believe the issues are financial and as such the airlines should be able to choose to fly subject to agreed boroscope inspections.

The media and people with a dangerous half-knowledge of aviation would have you believe that flight over the UK on Sunday 16th/Monday 17th May would have caused aeroplanes to fall out the sky. That in my opinion is boll**ks!

lomapaseo

20th May 2010, 23:56

The media and people with a dangerous half-knowledge of aviation would have you believe that flight over the UK on Sunday 16th/Monday 17th May would have caused aeroplanes to fall out the sky. That in my opinion is boll**ks!

I have another perspective

The "media" in the above statement is way too inclusive. I do agree however about the so called "half-knowledge" and it was exactly this point that resulted in the initial early May sense of caution excercised while the half-knoweldge was being converted to a better understanding of reasonable risk-tolerance actions.

The half knowledge still exists today among many, but fortunately those entrusted with the flight safety decisions have much more knowledge today. Tis true that the initial early actions were with an abundance of caution and in hindsight resolved themselves way too slowly. And many lessons were learned.

I get a better feel of where we are today by following what little print shows up in the mainstream of the truly international written media

PBL

21st May 2010, 06:27

Pace,

I am here to talk about volcanic ash, not to engage in repartee, but it seemed there was an implicit query in your last contribution as to why I and others don't simply accept your point of view. It might thus be worthwhile to tell you, just this once.

You suggest that you and sabenaboy and «most of the ATPs [whom you] know» think there is no hazard associated with flying «as usual» in the ash clouds.

To perform any risk analysis of the situation, one must do the following: (a) assess the chances that this is right; (b) assess the deleterious consequences that will follow (the «damage»; here we may take it that there is none); (c) assess the chances that this is wrong; (d) assess the damage in this case. Then one multiplies (a) by (b), and (c) by (d), and adds the results. We may take it that multiplying (a) by (b) yields zero because (b) is zero. So your assessment of risk is equal to (c) times (d).

That is the way it's been done for 299 years, and it seems to work. But far from attempting to estimate (c) and (d) in any way, you have mostly just disparaged people who have attempted to do so here. I conclude you know nothing about risk analysis. (Let me assure you further that the risk analysis of rare events is a tricky, indeed specialist, subject, to which I don't have the space here to do justice.)

So the answer as to why I, and others, do not accept your point of view is that you haven't attempted to perform the required analysis, so there is nothing yet to accept. It's as simple as that.

BTW, I made a conditional statement «if A then B», and you highlighted «B» and took me to be asserting it. We used to have fun with people who did this in school as follows. We used to say «if your nephew is a monkey then YOU ARE A MONKEY'S UNCLE! It's TRUE! Go ask teacher.» The victim would go ask teacher, who would then agree, yes it's true. And explain. Victim would thereby learn something. It seems schools have changed since then. Pity.

PBL

itsresidualmate

21st May 2010, 07:11

Right enough Loma, I should have said 'certain parts of the media'. Apologies for tarring everyone with the same brush.

Pace

21st May 2010, 08:45

(Let me assure you further that the risk analysis of rare events is a tricky, indeed specialist, subject, to which I don't have the space here to do justice.)

PBL

What better risk analysis can you have than 50 years of records and millions of flights?

The undisputable facts are that NO ONE has been killed in the whole history of aviation by ASH.

You are trying to do a risk analysis on something which to date statistically has shown NOT to be a risk.

There were two incidents where aircraft entered dense ASH clouds at night.
I am not talking about flying into dense ash cloud but flying in VMC daylight through ash concentrations which are so low that they are invisible to the human eye.

You have to differentiate between a threat or risk to life on which statistics over 50+ years show there to be none and a financial risk where there is a vague possibility that flying in low levels of ash or indeed any pollution may reduce the engine life. That is an accountants job not a health and safety issue.

If you want to do a risk analysis then great but look at areas which do have a record of continuing threat to life which we accept such as bird migrations sea based airports, weather winds etc etc etc.

My concern as a pilot would be flying into something which would cause an immediate failure in flight and thus cause me a problem. I do not believe until someone shows me otherwise that low density ash is a threat to causing an inflight failure.

If the engineers start posting here that they are finding ash damage which could cause that failure then I will sit up and listen but it hasnt happened yet.

But this is going round and round in circles and it maybe better to agree to disagree.

Pace

brooksjg

21st May 2010, 09:31

There were two incidents where aircraft entered dense ASH clouds at night....lets not go too far to under-state the risk.
There have been documented daytime 'incidents' involving damage to engines apparently caused by VA. Thankfully nothing involving any personal injury so far, most recently, the Finnish F-18 encounter - of which nothing much more has been reported. I don't recall reading what the visibility was at the time but I don't think it was at night. Presumably even military jet jockeys know not to fly through VA.

Also, lets not forget that this part of the discussion started with photos of a Cessna engine problem. This has already been quite thoroughly refuted by someone presenting themselves as a Cessna employee. Given the lack of any re-refutation in the original threads, this is now a Dead Letter. Why 'provenance' of a false rumour could be interesting defeats me. Maybe PBL should subscribe to the UK Daily Star for countless better examples that serve only to sell newspapers.

sabenaboy

21st May 2010, 10:08

...the Finnish F-18 encounter - of which nothing much more has been reported...

Well, I found this link to a flightglobal article:
PICTURES: Finnish F-18 engine checks reveal ‘no significant damage’ (http://www.flightglobal.com/articles/2010/04/23/341056/ash-cloud-pictures-finnish-f-18-engine-checks-reveal-no-significant.html)

Isn't it ironic that I came across that link after reading PBL's blog (http://www.abnormaldistribution.org/2010/04/28/the-political-economy-of-volcanic-ash/)? :p
I don't recall reading what the visibility was
True! I didn't find any information about the flight conditions of that F-18 mission. I'm interested to hear about it, but I would not be amazed if it wasn't by flying in clear blue sky that their engines were "not-significantly-damaged"!

Best regards,
Sabenaboy

PBL

21st May 2010, 10:14

Why 'provenance' of a false rumour could be interesting [to PBL] defeats me.

The "refutation" and "lack of re-refutation" have no more status than the original rumor. For hobbyists, this might be enough. For many professional purposes, it does not suffice.

PBL

BOAC

21st May 2010, 10:56

It looks from the synoptics as if there may be a drift towards the west of the UK by 25th.

GarageYears

21st May 2010, 13:10

Earthquake activity both at Eyjafjallajokull (many) and again two at Katla (the most recent occurring in the last 4 hours, while not very big at 0.4 on the Richter scale, was deep at 13.7km which is concerning).

Also just found out that the last time Eyjafjallajokull erupted it lasted for 14 months.... so this could be a long thread. :{

- GY

peter we

21st May 2010, 13:39

What better risk analysis can you have than 50 years of records and millions of flights?

The undisputable facts are that NO ONE has been killed in the whole history of aviation by ASH.

What a very strange thing to come out with. You could use the same logic with Concord; it had a perfect safety record, until it didn't.

Maybe its becuase aircraft have always avoided flying through dust, certainly when they do, in certain concentrations its got very very expensive and dangerous. And VA is not the same from all eruptions, some, like this, are far more damaging.

GarageYears

21st May 2010, 15:22

Another quake directly under Katla of 0.9 magnitude at a shallower depth 4.8km.

A bunch under Eyjafjallajokull.

-GY

lomapaseo

21st May 2010, 15:35

What better risk analysis can you have than 50 years of records and millions of flights?

The undisputable facts are that NO ONE has been killed in the whole history of aviation by ASH.

You are trying to do a risk analysis on something which to date statistically has shown NOT to be a risk.

Flight safety risk analysis does not work with extremely rare consequences.

What is done is to review much more common outcomes which fortunately for the passenger and crew are measurable degradation in safety (all nicely tided up in the definitions under 25.1309 and the Industry wide CAAM report published by the FAA.

Therfore even sucessful outcomes (the plane landed safely and the passengers changed their underwear) become part of the data. And nobody takes credit for events where nothing happened in millions and millions of hours but instead simply looks at the statistical probability that "any" degradation of safety (according to measured definitions) may happen that contains Volcanic Ash as an ingredient.

I keep saying that the volcanic conditions that we speak of today "will" result in some measurable degradation of safety but no more than the typical risk that we operate within everyday for all other causes (risk is never zero but it is managed within acceptable limits)

Most readers have no idea of what risk is allowed to underly each and every flight and the variable contributions of the causal factors versus time. Just because you identify a newly recognized causal factor "du jour" doesn't mean that you have to manage it to zero to justify to keep flying.

infrequentflyer789

21st May 2010, 17:13

And VA is not the same from all eruptions, some, like this, are far more damaging.

How much damage has this one actually done ? So far no one seems to have any confirmed damage.

Or do you mean that the response to the ash cloud was far more damaging (to the tune of a couple of billion) ?

kick the tires

21st May 2010, 17:27

an F-18's engine is like a ramjet when compared to todays hi-bypass engines; no wonder it picked up a load of VA!

jshg

21st May 2010, 19:49

Precisely ! The F18s would have been manoeuvring at high speed, high thrust, with no engine bleed worth speaking of, and probably at medium/low level. Under these circumstances they would have almost inevitably been damaged by ash ingestion.
Your average high-bypass commercial turbofan, on the other hand, operates at lower speed and relatively constant thrust, with air bleed. Our manuals tell us that in the event of an ash encounter we reduce speed and increase air bleed (and get the hell out of there).
The British government and authorities at the time of the original ash closure also mentioned an RAF Typhoon that had allegedly been damaged by ash. No doubt that was also manoeuvring at high thrust, low level, which bears no resemblance to the civil jet environment.

ILS27LEFT

21st May 2010, 20:42

Frequent but weak tremors in the area around our beloved Volcano in the last few hours, extending also to the proximity of Katla. Hopefully I am just over reacting and it does not mean anything at all.
The increase in seismic activity is objectively a fact in the last few hours but it seems normal activity intensity-wise, the location instead is a bit more worrying as epicentres seem to be moving towards Katla crater, but it could mean nothing, hopefully:uhoh::uhoh:

infrequentflyer789

21st May 2010, 22:47

The "refutation" and "lack of re-refutation" have no more status than the original rumor. For hobbyists, this might be enough. For many professional purposes, it does not suffice.

PBL

This looks to be an official note on the incident - I think someone already posted it ealier:

CEN10RA135 (http://www.ntsb.gov/ntsb/brief2.asp?ev_id=20100302X25146&ntsbno=CEN10RA135&akey=1) Note the date of the incident - it's pre iceland VA.

I doubt there have been two uncontained failures like this on the same type in less than three months (or rather, if there had I think it would have been bigger news and we'd know).

PBL: From this incident note and your professional contacts you may be able to confirm the details and tie in the photos - in which case the date and location rules out VA.

This may be as close as the rest of us amateurs get to an official statement (reported statement form Cessna): Engine Damage Not Caused by Volcanic Ash: AINonline. (http://www.ainonline.com/news/single-news-page/article/engine-damage-not-caused-by-volcanic-ash-24899/)

topper3

21st May 2010, 23:10

Latest update from the Iceland Met Office and Institute of Earth Sciences indicates that the explosive activity has died down considerably.

Articles < Seismicity < Icelandic Meteorological office (http://en.vedur.is/earthquakes-and-volcanism/articles/nr/1884)

:8:8:8

Chesty Morgan

21st May 2010, 23:17

at high thrust, low level, which bears no resemblance to the civil jet environment

Well except take offs, up to 10 a day for some of our aircraft, and go arounds.:D

And how can you say "no doubt" at low altitude and high thrust?

Pace

22nd May 2010, 01:38

I keep saying that the volcanic conditions that we speak of today "will" result in some measurable degradation of safety but no more than the typical risk that we operate within everyday for all other causes (risk is never zero but it is managed within acceptable limits)

Most readers have no idea of what risk is allowed to underly each and every flight and the variable contributions of the causal factors versus time. Just because you identify a newly recognized causal factor "du jour" doesn't mean that you have to manage it to zero to justify to keep flying.

Lomapaseo

This is a well written and thought ;) If you want zero risk DONT Fly.

There are far more PROVEN risky elements to flight than Ash yet ASH has cought the public imagination hyped by the media amd reacted to by a whole host of back watching Burocrats and quangos.

We have had many fatal landing and takeoff accidents in strong winds and shear conditions even within the "accepted operational levels" but do we have a long thread like this one demanding all takeoffs and landings should only be with zero wind?

Ash which has NO fatality record throughout aviation history has been hyped into a monster or bad wolf which is out to get you.

Maybe its becuase aircraft have always avoided flying through dust, certainly when they do, in certain concentrations its got very very expensive and dangerous. And VA is not the same from all eruptions, some, like this, are far more damaging.

Peter We

Volcanic eruptions are nothing new. Jet aircraft 20+ years ago had hardly any sophisticated equiptment and NO fancy computer generated Ash Prediction charts.

Maybe they flew through low level ash concentrations and never knew about it. If you cannot see it it wont hurt you.

Volcanic Ash really isnt a new phenomina!

Our MEDIA HYPE driven, paranoid, liability and blame culture IS!!!

Oh well off to bed so I can dream of shooting and killing a few million birds to save us from Bird flu!

but more likely to save us from ingesting them in our jet engines a real ignored threat.

Pace

PBL

22nd May 2010, 06:16

This looks to be an official note on the incident - I think someone already posted it ealier:

CEN10RA135

Thanks, IF! Yes, brother forget posted it earlier, along with a quote, and I missed it (the quote distracted me).

The pictures show an aircraft with a D-reg (can't see other letters), with engine, rear fuselage and tail markings identical to those on pictures on the WWW of some other Citations from Eisele Flugdienst. So I can call up the BFU, or indeed the company, and find out.

PBL

brooksjg

22nd May 2010, 09:18

I guess that a whole lot of the 'Ash Emergency' reporting from the Meeja generally is examples of 'Never let a Few Facts get in the way of a Good Story'.

Even the Flightglobal story reporting no significant damage to the F-18 engines, with a by-line of 23/4/10 was followed the very next day in the same magazine with 'Europe's volcanic ash response: was it adequate?' which mentioned the original 'reported' F-18 damage but not, strangely enough :rolleyes: , the previous day's 'no damage' story. I haven't ploughed through the literally 100s of VA references just in Flightglobal to try to judge their attempts to balance what was published but my guess is that they were also to some degree cheerleaders on the 'High VA risk - We're all gonna die' bandwagon. Given Flightglobal's position as an industry-specialist publication and particularly its own masthead (Serious about Aviation), this is disappointing.

It would be a bit of a stretch to envisage a conspiracy in which someone hijacked the NTSB website and planted a faked-up story about the Citation CJ incident so as to place it well before VA became an issue!!!

Pace

22nd May 2010, 09:44

BrookSJG

That is the sickening thing with the media they create the story they want and either ignore the facts or worse falsely make one thing appear to be another.

There are people who have had their lives ruined by the media by pretending something is true and painting a false picture to influence readers into believing it is true. Some of these people have been accused of horrendous crimes. When the courts find them not guilty that report gets a half inch column in the depths of the media report.

It is the same with this charade very damaging to aviation and made up of selective and false reporting designed to generate unfounded fear in the public.

These people including a select few in this forum should be ashamed of themselves as all they achieve is damaging an industry and peoples livelyhoods by their false representations. Worst is most dont even know what they are talking about.

Pace

tea & bikkies

22nd May 2010, 10:15

Interesting to see the nature of this ash, note the chunky structure.

Eyjafjallajökull ash under a petrographic microscope in crossed-polarized light (http://www.microscopyu.com/articles/polarized/polarizedintro.html) at ~40x. Image by Erik Klemetti.

http://i726.photobucket.com/albums/ww269/greg2217/Eyja_ash8_xn_labeled-thumb-400x300-.jpg

Eyjafjallajökull ash under a petrographic microscope in crossed-polarized light (http://www.microscopyu.com/articles/polarized/polarizedintro.html) at ~100x. Image by Erik Klemetti.

http://i726.photobucket.com/albums/ww269/greg2217/Eyja_xn_ash2-thumb-400x300-49461.jpg

BillS

23rd May 2010, 17:34

Icelandic Met Office reporting (http://en.vedur.is/earthquakes-and-volcanism/articles/nr/1884) marked decrease in activity:
The eruption activity is minimal and therefore no significant ashfall is expected. The volcano is still being monitored and an ashfall forecast will be issued if neccessary.
Visibly very different! (http://http.ruv.straumar.is/static.ruv.is/vefur/23052010_eldgosi_lokid.wmv)

brooksjg

24th May 2010, 00:07

Now that the dust has settled (at least for the moment!), has anyone seen any proper explanation (especially from the Met Office) for the overall lack of accuracy of VA Forecasting and, in particular, for the error(s) that led to the sudden and very obvious revision between 0600 and 1200 last Monday (17th May)?

Quite apart from the disruption caused by lack of inbound flights to LGW and other short-term problems, there was also a potential risk (already mentioned above) from reassignment of certain areas of the North Sea from 'white' to Black in the same revision.

Superficially, it looked like inaccuracies in weather forecasting had been allowed to 'bleed through' into the VA Forecast, with no later corrections being applied as real weather data superseded the forecasts. I have no actual evidence of this but unless something like this occurred, how could such a major restatement of the position of the ash cloud ever be required? - unless, of course, there were other problems with the model that only came to light over the weekend 15/16th May.

lurkinginSTO

24th May 2010, 06:25

No, visibly is exactly what the report is saying... there is visibly only steam production, and other signs show that the eruption calmed down... How long, it's impossible to know, though. You can hardly see it on the cameras. Let's hope this is it!

peter we

24th May 2010, 09:07

I have no actual evidence of this but unless something like this occurred, how could such a major restatement of the position of the ash cloud ever be required? - unless, of course, there were other problems with the model that only came to light over the weekend 15/16th May.

There was nothing wrong with the model or the forecasting, they were obviously told to change it, by the new government, to allow the airports to open.

brooksjg

24th May 2010, 10:43

There was nothing wrong with the model or the forecasting, they were obviously told to change iterrrr....

The Powers That Be can (easily) change the specified minima/maxima for any given situation, so long as the new value remains inside other legal / regulatory limits that may apply. They already did this - by going from 2000 to 4000 micrograms/cube (with additional caveats). They did not need to get the VA forecast 'adjusted' as well. IMHO it would have been extremely foolhardy to even try to do so: someone could easily have other, more accurate evidence and/or might want to saddle the originator of the request/order with all the responsibility (and potential blame). In this situation, a leak to the media would be a virtual certainty! For a recent example of this, see Climate Change 'emails scandal' at the University of East Anglia. A bit of tinkering with climate data and months later, after an external enquiry and at least one Severely Career-Limiting Move, they're still chipping brown solids off the fans! Especially with this recent example to learn from, I'm surprised the Met Office has so far failed to come clean about the forecast!

So why were the limits and the VA forecast both adjusted, at very similar times?? (I still favour cock-up over conspiracy but have no better information myself.)

That said, it's also quite entertaining to watch the various regulators' heads popping above / below the parapet, depending on whether they reckon they'll catch blame (or have to take responsibility!) if ultimately something goes legs-up.

BOAC

24th May 2010, 11:43

Peter - there most certainly did appear to be a forecasting error. As brooksjg and I have pointed out, there was a sudden shift of the 'black ash' area from over the middle of England out into the 'clear area' where unsuspecting a/c had been happily toddling along.

Nemrytter

24th May 2010, 12:26

Think about it. The VAAC issue one forecast every 6 hours, and if we examine these forecasts since the beginning of the 'ash crisis', let's say 60 days ago, then there is only this one obvious error on May 17th.

60x4=240 forecasts. One of which is wrong, that's 0.4% of the total. Not a bad accuracy level, to be honest.

Forecasts will always be slightly wrong. The forecast you see on something like the VAAC is merely the most probable outcome. The prediction system typically generates a number of possible forecasts and assigns a probability to each that determines how likely it is to occur.
Perhaps on the 17th there were two with very similar probabilities, and the VAAC staff got unlucky and chose the wrong one. Or perhaps they chose one that was very likely, but for some reason one of the more unlikely predictions turned out to be true.

BOAC

24th May 2010, 12:52

Not that simple, Simon (as they say.:)). The 'incorrect model' went on for days, drifting the ash down to where it wasn't. Suddenly when a huge fuss erupted - bingo!

A touch more than .4% - and that is assuming that the previous ash disposition charts were all spot on!

peter we

24th May 2010, 15:43

60x4=240 forecasts. One of which is wrong, that's 0.4% of the total. Not a bad accuracy level, to be honest.

Yes, and by coincidence the 'error' happened to close down the major SE airports. Fixing it allowed them to re-open.. what an amazing piece of luck.

brooksjg

24th May 2010, 16:13

Yes - not necessarily one 'incorrect' forecast - a whole series of totally consistent forecasts, over at least 3 days, showing movement South / South-eastward and gradual expansion of the cloud's area.

I'm just digging back through the raw mapping data to try to understand better what happened......

Sunfish

24th May 2010, 21:53

Frankly, as I've said before, I thought the whole event has been handled very well. There will undoubtedly be review and analysis of what could have been done better, and of course with 20/20 hindsight there will undoubtedly be room for improvement.

However that does not change the fact that a response to an unforeseen event - the possibility of a major volcanic ash cloud disrupting the worlds busiest intercontinental air routes, has been handled very quickly, considering the coordination required, with minimal disruption to the travelling public.

Well done to the industry as a whole! You are in a better armed state to face the next challenge when it arrives.

brooksjg

24th May 2010, 22:45

You are in a better armed state to face the next challenge when it arrivesBased on most recent events, I beg to differ. We're more likely at a 'Rumsfeld Moment', when it's become apparent that there are some extra Known Unknowns which either didn't matter previously or were Unknown Unknowns.

Realities are that a (small) volcano has stopped erupting for now and the big one (Hekla) has yet to start. Meantime, we still have no quick, accurate means to locate and measure volcanic ash in the atmosphere, and therefore depend on computer modelling, which in turn depends on accurate data from forecasts and actual weather in the recent past. As was demonstrated last week, modelling can fail and each time it does the unnecessary financial cost to the industry is very large and/or aircraft could be damaged.

Not much of a moment for congratulations. And to say that we're 'better armed' only applies to defensive reaction time when ash is predicted, with little improvement in prediction accuracy or avoidance of the problem. There must be potential improvements in sensors and other detection strategies but little evidence at the moment of any concerted effort being applied.

Sorry to rain on the parade but that's the way it is.

Sunfish

25th May 2010, 06:21

Brookes:

Meantime, we still have no quick, accurate means to locate and measure volcanic ash in the atmosphere, and therefore depend on computer modelling, which in turn depends on accurate data from forecasts and actual weather in the recent past. As was demonstrated last week, modelling can fail and each time it does the unnecessary financial cost to the industry is very large and/or aircraft could be damaged.

Not much of a moment for congratulations. And to say that we're 'better armed' only applies to defensive reaction time when ash is predicted, with little improvement in prediction accuracy or avoidance of the problem. There must be potential improvements in sensors and other detection strategies but little evidence at the moment of any concerted effort being applied.

Sorry to rain on the parade but that's the way it is.

If you want to attempt to forecast where ash is, then your industry can pay for it.

Meanwhile, in Two weeks from the start of the event, the airframe manufacturers, engine manufacturers, airlines, regulators, lawyers, vulcanologists, meteorologists and insurers of many nations worked together to produce a set of operational protocols that worked.

I'm sorry if they weren't to your liking, but the fact is that they are an achievement and can be deployed again if necessary.

Bear in mind that the consequences of a major part of the Transatlantic fleet, for want of a better word, getting their engines seriously damaged by Ash ingestion would have been months of cancelled flights as there is not enough engine overhaul capacity on this planet to deal with an emergency workload of that magnitude.

We cater for the odd bird strike, not 200+ airliners needing four overhauled engines at five minutes notice. Please try and understand that that is the logistical nightmare behind the need for regulation and prohibition.

brooksjg

25th May 2010, 09:05

If you want to attempt to forecast where ash is, then your industry can pay for it

Part of the purpose of my last post was to highlight that the industry has done nothing except react 'passively'. Whether this reaction was adequate or technically sound is debatable. Anyway, we have some breathing space while the volcano(es) go(es) quiet and we await the next eruption - expert opinion suggests there will be one, possibly soon.

So what about ash detection? Seems that the only really effective method is to fly an aircraft along a track where VA might be and use lidar and / or sampling to check what's there.

Cost? Really doesn't matter! NOT doing this results in potentially unnecessary shutdowns of airspace, airports and sometimes the whole of UK air transport, with calculable cost x per hour or day. So long as the cost of an accurate forecasting / alerting system is less than a fraction of x, it's worth doing. (fraction calculated from the probabilities of future eruption(s) and of false VA alarms.)

Risk? You can't ask people to deliberately fly research aircraft into high risk areas when there is no accurate VA data.

However, there is a suitable platform for doing just this, at negligible risk to people. Predators with all sorts of fancy sensors (and Hellfires!) are already flying reliably in various places. Why not rip out as much of the expensive bits as possible from some Predators (or another suitable UAV), plus whatever classified bits have to go, mount instead some suitable LIDAR, SO2 sensor and whatever other sensors and samplers would be useful, plus civil transponders, and use them as a picket line somewhere off NW Scotland / Ireland? Flying orbits using (say) 4 aircraft round the clock at various heights in an otherwise-vacant bit of airspace would yield very accurate data on what was heading towards UK. If all else failed, monitoring the in- and post-flight engine condition of the engines would also provide good data.

Why not? - We'd only need to fly the picket line as such when we knew that an eruption was happening. We know where the risk will be coming from. Rest of the time, the UAVs could be used for (military) training in the use of the UAV platform and occasionally checking that the system worked with a quick trip close to a volcano.

OK - would not prevent disruption altogether but would minimise it. And much better than doing nothing proactive!

BOAC

25th May 2010, 11:29

Risk? You can't ask people to deliberately fly research aircraft into high risk areas when there is no accurate VA data. That is exactly what was done with commercial aircraft carrying passengers that were routed over the North Sea (where the ash 'wasn't') and kept away from the mainland areas (where the ash 'was').

If this is considered acceptable why not fly samplers in the areas where the ash 'isn't' to confirm the forecast?

The SSK

25th May 2010, 11:48

Sunfish: We cater for the odd bird strike, not 200+ airliners needing four overhauled engines at five minutes notice. Please try and understand that that is the logistical nightmare behind the need for regulation and prohibition.

It is NOT the job of the Regulator to regulate on issues of commercial judgement, which this is. Safety - yes. Logistics - no.

Sunfish

25th May 2010, 21:31

Brooks:

Part of the purpose of my last post was to highlight that the industry has done nothing except react 'passively'. Whether this reaction was adequate or technically sound is debatable. Anyway, we have some breathing space while the volcano(es) go(es) quiet and we await the next eruption - expert opinion suggests there will be one, possibly soon.

So what about ash detection? Seems that the only really effective method is to fly an aircraft along a track where VA might be and use lidar and / or sampling to check what's there.

Cost? Really doesn't matter! NOT doing this results in potentially unnecessary shutdowns of airspace, airports and sometimes the whole of UK air transport, with calculable cost x per hour or day. So long as the cost of an accurate forecasting / alerting system is less than a fraction of x, it's worth doing. (fraction calculated from the probabilities of future eruption(s) and of false VA alarms.)

Risk? You can't ask people to deliberately fly research aircraft into high risk areas when there is no accurate VA data.

However, there is a suitable platform for doing just this, at negligible risk to people. Predators with all sorts of fancy sensors (and Hellfires!) are already flying reliably in various places. Why not rip out as much of the expensive bits as possible from some Predators (or another suitable UAV), plus whatever classified bits have to go, mount instead some suitable LIDAR, SO2 sensor and whatever other sensors and samplers would be useful, plus civil transponders, and use them as a picket line somewhere off NW Scotland / Ireland? Flying orbits using (say) 4 aircraft round the clock at various heights in an otherwise-vacant bit of airspace would yield very accurate data on what was heading towards UK. If all else failed, monitoring the in- and post-flight engine condition of the engines would also provide good data.

Why not? - We'd only need to fly the picket line as such when we knew that an eruption was happening. We know where the risk will be coming from. Rest of the time, the UAVs could be used for (military) training in the use of the UAV platform and occasionally checking that the system worked with a quick trip close to a volcano.

OK - would not prevent disruption altogether but would minimise it. And much better than doing nothing proactive!

Off you go then and develop your little program and pay for it yourself. The operational regulations about avoiding ash clouds in real time while maintaining separation standards with other aircraft all doing the same thing should be a highly entertaining read, as will those regarding diversions and emergency procedures.

Your accountants will perhaps chafe a little while these expensive standards gather (non - volcanic) dust sitting on the shelves waiting for the next Icelandic eruption, and if it's a big one from Katla, and the wind is in the wrong direction, then all your little cheese paring standards aren't going to be much use are they? In my opinion, the reaction of the regulators was measured, proportionate, prompt, cost efficient and minimised both risk and disruption to the public to a bare minimum.

SSK:

It is NOT the job of the Regulator to regulate on issues of commercial judgement, which this is. Safety - yes. Logistics - no.

It is not the job of the Health Department to monitor your personal health either, but when an epidemic potentially occurs the Health Department rightly steps in.

A single engine failure is a matter for your airline. An epidemic of engines all turning up at the "Hospital" at once is a matter of public concern regarding provision of RPT services and hence regulatory action.

To put it another way: An ounce of prevention is worth a pound of cure. Saying "No" and grounding you until we are relatively certain you are safe is the simplest, cheapest and most direct safety action.

brooksjg

25th May 2010, 22:00

regulations about avoiding ash clouds in real time while maintaining separation standards with other aircraft all doing the same thing
Huh????

I NEVER suggested anything of the sort.

My observation is that the VAAC forecasting can be inaccurate, as was especially obvious on 17th May. There is some technology (UAVs with suitable sensors) that could be used if the airlines wish to avoid losing revenue due to unnecessary shut-downs when in fact there is not enough VA to be a problem (although 'tolerable' ash density presumably still awaits final agreement...) or it's in places where it can have no effect. A way this could be funded is via contributions from companies at risk of major losses due to VA - it's a business calculation for them what measures would be cost-effective. From where I'm sitting, it looks like an excellent investment in the absence of any other improvement to the forecast....

How my suggestion could refer to aircraft playing officially-sanctioned 3D Blind Man's Buff I'm unable to explain! I was only suggesting a method to improve VA mapping, nothing to do with subsequent use of the resulting maps.

lomapaseo

25th May 2010, 23:38

It is NOT the job of the Regulator to regulate on issues of commercial judgement, which this is. Safety - yes. Logistics - no.

It is not the job of the Health Department to monitor your personal health either, but when an epidemic potentially occurs the Health Department rightly steps in.

A single engine failure is a matter for your airline. An epidemic of engines all turning up at the "Hospital" at once is a matter of public concern regarding provision of RPT services and hence regulatory action.

The difference in interpretation between these two quotes is based on measurements of risk/ safety not grounded against costs. As a read of the FAA engine guys release weeks ago, suggests, the measurable risk had not increased to the point where Continued Airworthiness action was warrented.

Just because some suggest that there is an epidemic on the horizon does not mean that it will actually occur (SARs etc.). So like other concerns watching, measuring and a measured response in avoidance seems to be the best action all of which is being practised.

Pace

26th May 2010, 00:04

Sunfish

To put it another way: An ounce of prevention is worth a pound of cure. Saying "No" and grounding you until we are relatively certain you are safe is the simplest, cheapest and most direct safety action.

On what basis or knowledge do you make your fanciful and wild statements?
Frankly Sunfish you do not have a clue what you are talking about.
Do you not think that the Airline industry would not jump at the so called "cheapest" option as you declared?

The biggest flaw in computer mapping of VA is that VA density is no more consistant than any cloud.

You could take an area of 10,000 sq miles of ash contaminated air estimated as being within the approved density levels and there would be NO consistancy in that area.

Some patches would be way below other patches would be way above.

Any particles in the air of enough area and density will show to the naked eye in a cloud or mist form. The only practical and accurate way to avoid flying into dense ash is to avoid flying into visible cloud especially pollution coloured cloud.

Stick in clear air by using the normal CB avoidance of requesting a left or right deviation is the only practical and reliable way of keeping clear of dense ash which "could" cause you an inflight engine problem and of course avoiding flying at night.

As to minute density areas of ash which are in thin mist form or not visible then the only practical way is to check those aircraft for pollution damage on a regular basis.

As for your doomsday scenario forecast of 100s of engines needing major maintenance that is equally fanciful and not showing any evidence to date.
Until the day that qualified engineers start reporting such damage I am afraid that your comments will stay in the fanciful and in your dreams bin.

If that ever happens and I doubt it then I will take my hat off to you and say that Sunfish was right.

I would also like to ask you what your background and knowledge is that justifies your wild assumptions?

Yes I do think the current VA forecasting is seriously flawed and innacurate and that also is proving to be true.
Please also differentiate between what is a threat to flight and a threat to bank balance.

The threat to bank balance will be best determined by the airlines as probably will the threat to flight by pilots and airlines and engineers not some burocrats, politicians or quangos with their own agendas and back covering foremost.

Pace

Sunfish

26th May 2010, 02:17

Nothing I have said is wild or fanciful. I've watched the build of plenty of engines and I assure you it does not happen overnight. Do you know for example what tip grinding is? Do you know how many tip grinding lathes are around? Have you ever seen people at the bench individually hand finishing blades and vanes?

Do you understand that when the evidence of which you speak appears, it is too late for that engine? Don't you understand that engines take a long time to build?

Do you understand the consequences of being wrong and not applying the precautionary principle? I do not think you do.

PBL

26th May 2010, 08:33

There is some technology (UAVs with suitable sensors) that could be used if the airlines wish to avoid losing revenue due to unnecessary shut-downs ....

This is an impractical suggestion for the short- or medium-term. As far as I know we are not even close to regulations governing the general flight of UAVs in civil airspace. This is a very hot topic at the moment, and we are a ways yet from any sign of consensus.

PBL

The SSK

26th May 2010, 08:36

Sunfish: Do you understand the consequences of being wrong and not applying the precautionary principle? I do not think you do.

Your argument is based on an assumption that airlines are too stupid to recognise this, and therefore need civil servants to tell them what they can and cannot do.

John47

26th May 2010, 08:44

NASA has posted an example of satellite and lidar observation of ash clouds for 16 May.

As NASA puts it
One reason for widespread closures was the challenge in knowing where the ash was. Many satellites can provide a bird’s-eye view (such as the top, nighttime image) that can identify thick plumes of ash, but few satellites can tell how high the ash is in the atmosphere. The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) satellite, however, records a vertical profile of the atmosphere, which reveals the altitude of ash clouds, shown in the lower image. These observations help modelers in volcanic ash advisory centers improve forecasting models and issue more accurate warnings to pilots and others with aviation interests.

Nighttime Ash Tracking with CALIPSO : Image of the Day (http://earthobservatory.nasa.gov/IOTD/view.php?id=44052)