S

I think the argument was more about to many cooks and the fact that the tests needed to relax the "rules" could have been done days ago if what was said on the BBC was anything to go by.

Another reason why there has never been a statue made of a committee

Yes there will be a big row over who pays and maybe with some justification an expensive lesson to be learnt all round :sad:

Pace

The number of pompous punters here who are outraged that airspace was closed at all because the problem doesn't really exist is irritating.

The number who wonder why "tests" weren't done immediately is frightening.

The number who believe that the Government vacillated over decision making after tests and consultation is mind boggling.

Let me make a number of things quite clear.

1. The problem is real. Yes, I know volcanoes erupt all over the world. I know that there are sand storms in the Desert and dust in the air. I know intrepid pilots fly around erupting volcanoes. I know that some European airports remained open. The problem however is that this particular dust from this particular volcano thanks to this particular weather system stuck itself in large quantities over Britain, and it has the capacity to bugger up very expensive jet engines that are not quickly replaceable by the manufacturers. I know you paid your Twenty quid to get to Paris, but I am not going to risk wrecking Ten million dollars worth of engines to get you there today.

2. Tests were done immediately. Do you think the Government keeps a jet already wired up and on standby to test for volcanic ash? Is there a submarine kept ready and waiting to check the ocean floor for undersea earthquakes? Of course not. Tests were carried out. Did you know it takes time to design a test? It also takes time to prepare for a test and then analyse the results.

3. Vacillating Government? Tests had to be done. Manufacturers had to be consulted. The results of the tests had to be analysed. There are also regulatory frameworks that must be followed because they have the force of law. This takes time. Do you expect the Government to take a billion dollar bet without proper advice, just so that you can get your sorry backside to Amsterdam to smoke dope? I happen to think that Five days from whoa to go is a pretty snappy response where a technically, scientifically and operationally complex decision has had to be made.

Furthermore, next time the airspace is closed again because of this or other eruptions, you will have no further grounds whatsoever to complain.

Thank you to the person who posted the high resolution images of the F404 nozzle guide vanes and first stage blade. I have to take issue with your view that there was "no damage'. To make that statement would require the sectioning of at least one each of those hollow components to see what has been deposited internally, as it is internal build up that will have the most effect on blade and vane cooling.

Clear blue skies.
 

Hi Sunfish

The problem is that for the past week in the UK we have had brilliant, clear blue skies. In 1940 we had the same. Then the sky was full of aeroplanes. Our parents called it Battle of Britain weather.

This past week the sky has been empty of aeroplanes. Brilliant, clear blue skies. Volcano weather! Well, that is how I shall remember it.:)

Regards

S

Sunfish

I was flying a business jet up north hours before the airspace was closed if you PM me I will give you a link to a video I made from the cockpit.

Beautiful day 100 miles vis at FL250 with well pronounced and broken cumulus well below.

The MK1 eyeball is the best way of detecting particles either water or dust. Clear air is clear air. I find it hard to understand claims of invisible.
Pollution in dust form is visible to pilots either as a haze or thin cloud and usually with a slight colouration.

I take your point on looking vertically but horizontally NO unless of course your in cloud or flying at night.

Did the various groups involved do their best within the regs without doubt

Were we victims of our own burocracy possibly? I also take the point of hindsight and could things have been done differently.

Regardless there will be finger pointing as the huge cost and who bears it hits the courts.

Pace

BA 747 and Ash Clouds
 

I heard a roumor that this incident when it lost its engines one of the crew was out walking around the cabin at the time. It was saved by the Flight Engineer and the other pilot, is this correct, if it is, what a fantastic effort by those on the flight deck!!

From Wikipedia:

British Airways Flight 9 - Wikipedia, the free encyclopedia

Pace:
of course you are right: a well trained or experienced eye will see the ash in the clear air. It has been cleary demonstrated by german and british research flights where lidar measurements were taken.
The question is how to standardise or validate the eye sightings against any definite level of aceptable ash contents in the air. The right answer was given in the documentation from the engine manufacturesre: avoid ANY area are where there is detectable ash. And since clouds do happen even in England ;) the NATS/CAA approach was justified.

Don't forget that WW is effectively responsible for the zero figure due to the airlines long standing refusal to provide provide an alternative figure.

He is also partly responsible for the chaos as he must have been fully aware of the risk of an Icelandic eruption and the potential effect it would have had on the industry - but did nothing to mitigate it until after the issue became a real problem. That indicates piss poor planning.

Sooooooooo how long was that Finnish Air Force F-18 up?

Did it do multiple sorties transiting the ash clouds several times climbing and descending for eight to ten hours a day like a B-737 would or did it stay local for only an hour or two and then got it's wings clipped?

As the weather has changed we'll never know.

@anotherthing
Make up your mind.

Either it is "ridiculous and ignorant" (your words) to accuse the authorities of not being competent, or it is not. Or perhaps you are only accusing them when they don't agree with you?

Personally, as SLF with a cancelled business trip to a country that is well used to both volcanoes and crashing planes, I don't care either way, but at least be consistent.

WojtekSz, Pace:
You both have wrong underlining assumption: That ash is only possible pollutant in the air. It is not possible to differentiate between dangerous pollutant - ash - and anything else.

Sunfish -- Wise advice.

Pace --As someone living in an area with a huge pollen count every Spring, including now, clear air and blue skies do not stop me from teary eyes, runny nose, and sneezing, even if I can't see what I'm breathing.

The picture of the tiny vents use to cool the turbine blades gave me pause for thought, as have comments on the possibility of pitot tubes clogging.

After all, isn't the Air France crash in the mid-Atlantic attributed in part to misleading air speed from pitot tubes clogged with ice? What's the difference between ash and ice, aside from clear skies and sunny weather, and the relative (?) ease of switching to VFR?

Where have I assumed that ash is the only pollutant in the air? I do assume that any pollutant which is dense enough to cause a problem will be visible in clear air.

If you are flying in an area with known volcanic ash I would assume the worst and that any pockets of mist or thin cloud especially with a pollution colouring is likely to contain ash and would avoid flying for prolonged periods in such pockets.

Equally a pilot will avoid flying in visible moisture ie cloud at temperatures of zero or below when that cloud is icing up his aircraft.
He will climb descend or avoid to get out of the icing situation.
As long as the pilot is visual his best means of detection are his eyes. most of this week above 5000 feet there has been very little cloud over a large portion of the UK and below 5000 feet well broken cumulus with suoerb visibility above.

One is a solid particle the other is formed from a liquid and is accumlative they are very different in form and how they react with the airframe.

Pace

Some you see, this you don't
 

Early posts on this thread appeared to establish that the far-travelling ash from that phase of this particular erruption was effectively transparent to both visible light and the radio frequencies used by weather radar. It did reflect, however, at some infra-red wavelengths. So despite the visually clear skies, the nasties were there and the Mk1 eyeball was unable to detect them. The first D-CALM flight reported this - also saying that it avoided flying into stuff that could be detected only by its special atmospheric research kit.

Enginebiz....
 

1+



Yes, Count, and what little we DO know about ash cloud events, no I should say we know a lot, and ALL the flying that took place from Monday on and yesterday and in some parts today was ONE HUGE ASH CLOUD penetration experiment...( not yet Darwin Awards quality but damn close...)

The avalanche is yet to come..

The vulcano will be quiet, the media attention will have vanished...

BUT engines that got their share of ash all over Europe either slightly before the closure or now at this time, since Monday and especially yesterday,

well those motors may start to cough pretty soon..

Loaner engine pools will be depleted very soon because of high demand and the fact that most investigating, even if no big engine damage is found, will need shop visits..

and lest anybody may think there was no cloud...sure there was and partly still is....and there is stuff in there..the kind of ugly stuff that engine manufacturers rightly say MUST NOT BE INHALED by the motors in ANY concentration...

We never know, it may yet turn out that giving it one or two more days before restarting full flight ops would have been the more cost effective solution for the operators..

let's say you have a 100 737s or 320s....lets say a third of your fleet needs some premature engine work because of yesterdays flying...lets say 60 motors at roughly 1 - 2 Mio USD per motor for DR & performance restoration...

well that's, let's make it easy that's a cool 100 Mio USD +

You dont lose a 100 Mio a day if your park 100 birds for two days...

But it will take a long time to earn enough to have those 100 MIO back on the plus side of your balance sheets..

and that is just the commercial aspect of it...

We have not talked safety yet...

For those who are interested in the details, the Finnish Air Force sent 5 Hornets up in the morning of the 15th for "one dogfight training sortie" at altitudes of 18000 ft and below. Duration is not given but the mission covered several hundred square km. On return to base, clearly visible layers of flour-like dust was discovered around the air intakes of three of the five a/c, after which it was decided to perform a thorough examination to determine the extent of damage if any.

A pdf file of slides used in yesterday´s press conference here (language only in Finnish):

http://www.ilmavoimat.fi/filebank/5377-tuhkatilanne.pdf

The latest is, engine components with particle concentrations will be replaced and said components will undergo further tests.

At last some Numbers
 

p4 todays Grauniad quotes one Jim McKenna, (CAA's Head of Airworthiness) and in a long, well written and balanced (IMHO) summary states, inter alia:

Initial no-go areas defined as those the model predicted to have more than ten billionths of a gram per cubic metre.

After tests and consultation with Airframe and Engine manufacturers:

1. Anywhere with more than 2000 micrograms/cu.m. = No Fly
2. 200 - 2000 micrograms /cu.m. = Can fly with 'precautions', taken by me to mean extra inspections, particularly of engines.
3. < 200 micrograms / cu.m = no threat.

Enjoy, I'm off to MXP.:)

The airspace closure was done by NATS, not HMG, and only to IFR flights in class A airspace. Several jets (private / small charter) left U.K. airspace on Thursday and Friday VFR, low level. By Friday evening CAA (the governing body) were still advising that NATS closure was recommended and that if people tried to circumvent it a more general closure would be put in place.

Presumably, sometime over the weekend, CAA took charge? Otherwise , how did it become the case that it was the CAA spokeswoman outside of the DFT on Tuesday evening rather than a NATS spokesperson?

Pace Thank you for your reply. The point I tried to make was that if this ash can clog the pitot tube, that's a problem. The possibility was mentioned when the ash cloud was thicker.

Are the current VAAs issued with the "ten billionths of a gram per cubic metre" delineation?

Or are they defined as being >200 micrograms per cubic metre?

Those Advisories are still being issued and the ICAO requirements still exist (if only on paper). We can still be held liable for contravening the ICAO guidelines if we incur serious consequences, so we should know what those advisories actually delineate.

DairyGround

I read that too but it depends on how you interpretate it. We all saw the billowing dense black cloud spewing out from the source of the volcano.
Are the so called experts telling us that all those amazing pictures we saw were infact invisable to the naked eye because volcanic ash has some AMAZING property which defies the laws of Physics.

If so they should cover Stealth Bombers in the stuff :ugh:

Any Particle liquid or solid will reflect light. We all see clouds we all see vapour trails made up of tiny ice crystals. we all see dust clouds.
Try landing in Saudi Like I did in 2000 metres dust Which after landing
turned into a sandstorm with 100 metres its all visible.

If we take the zero tolerance of volcanic ash theoretically one partical would make it illegal and of course we would not see one particle anymore than we are likly to see one wasp 100 metres away but we will see a swarm.

We in this country are victims of media hype you only have to see the terror inflicted on us as the so called experts predicted 65000 deaths from Mexican flu. People were paying £500 for a small pack of Tamiflu The government advised by experts bought up £2 billion of the stuff. result 346 deaths less than a normal flu and £2 billion of Tamiflu they cannot give away. We can all remember many such scares whipped up by the media and predicted by the science.

So yes Volcanic ash in reasonable density will be visible but dispersed to literally nil will not.The big question is whether literally nil will do damage

Pace

MOL has been "encouraged" to back down and pay expenses to Ryanair travellers after all of the gusto and bravado that spewed out this morning, I guess, has else why would they know do a 180 and agree to reimburse in accordance with EU regs. (Just on Sky now).

Orions belt . The ICAO was very actively trying to raise the limit up to one month ago. There was a working group set up in 2008 to study volcanic ash. That working group made representations to all parties concerned and encouraged them to attend a conference about a month ago. They specifically asked IATA to survey airlines on how they viewed the risks and what levels they might accept. IATA did not attend the ICAO conference instead reporting that although it had canvassed all member airlines heavily sadly none had responded.

Airlines are running around willy nilly now saying nobody would take a decision in the nanny state etc. when in fact they had an opportunity just a month ago to report what ash concentration they themselves were prepared to accept ( having had a long time to study and consider the matter given they were first asked for input in early 2009 ). For fear of legal consequences it seems they did not respond. They seemed fearful of setting a number and then having an incident if that number was too high ( in terms of acceptable concentration ). I think when it call comes out ICAO will be spotless and the airlines themselves a little red faced.

Paidworker

None of the above is normal or standard RT Phraseology. You do not talk about "serious" CAVOK! You may talk about a serious smell of burning but unless the pilot was familiar with the smell of ash which is unlikely a smell of burning could come from another source within the aircraft. In all probability a serious smell of burning would require an immediate landing as it would be a potential emergency situation and nothing to do with whats outside the aircraft.

The pilot using the word serious attached to both sounds more like a windup a joke which does happen in the airways.

On a slightly different note smells in an aircraft can come from the ground. I can remember flying a twin prop in IMC over a biscuit factory. The delicious smell of biscuits was almost a locator of where we were as I flew that route many times ;)

It is also worth considering that in any heightened and cautious state the mind plays tricks. fly a single over long stretches of water and its amazing how rough your engine suddenly appears to be.

Pace

For Pace and all the others who persist with this nonsense that they can 'see' this contaminant when they fly.

The only way you can 'see' it in the air is at night with a torch shone up into the sky. Try it. Over the last few days, just south of LGW, the sky was stuffed with flurries of small particles. There were slightly less last night. You are breathing them in by the million all day. They will lodge in your lungs and cannot be removed. Your engines will ingest them. Whether they are dangerous I know not, but do not be fooled by clear blue skies. Look at your car?

I think asking the airlines is asking the wrong people
 

I can see why the questions about acceptably safe ash levels went unanswered. From the safety standpoint the manufacturers surely are the right people answer that question, NOT the operators.

The airlines can answer a lesser economic/commercial question, such as 'how much wear and inspection can you live with?'

'How much gunge is up there, what is it composed of and where is it?' is surely a question for the MET people.

'Can you accommodate routing flights around this gunge?' is a question for the Air Traffic Services people


I believe there are also questions to look at regarding pax compensation, insurance and priorities for travel.

I don't think the existing compensation rules make much sense. People who are stranded away from home clearly need compo for accomm, but people who are merely delayed in their home country probably don't. I don't see why airlines should be compensating for weather, including ash, unless there is a humanitarian need or the journey has started but hasn't been finished.

Insurance cover that's void is clearly a problem to address- otherwise people quite rightly won't buy it. We need an insurance system that's functional, then the airline funded compensation problem is a lot smaller. Actuarial and underwriting systems exist so I cannot see why we have to allow insurers to weasel out.



Finally although I'm a lucky person with a booking which replaces a kangaroo route trip scheduled for 2 days ago... I can't help thinking that slavishly honouring bookings for flights that operate at the expense of people who were unlucky enough to be on cancelled flights is a worry.

Maybe as a minimum people with good bookings could be asked if they will give them up, possibly in return for an inducement such as an upgrade or money. That way people who urgently need to travel might stand a chance of getting on, especially if they (or their insurers) are content to pay extra.

BOAC

PLease read what I said. Yes you can see see particles liquid or solid in the air.

You know that.

If they are so dispersed to a very low level NO you wont see them.
That is the very arguement which opened up our airspace. At what level of density does ash cause a hazard.

That has been raised and may be raised again or lowered as more data comes in from normal operational aircraft.

Pace

BOAC
 

Pollen? It's that time of year. What is showing up in the horizontal beams from landing lights?

Regards

S

- if pollen smells of Keflavik tapwater then you've got it sorted!

Hi Pace,

I was referring to this the atc recording from yesterday and making no inference as to whether the pilot was being tongue in cheek with the use of the word " serious " or indeed if he was mistaken about the strong smell being that of burning ash although he clearly felt he wasnt.

edited : removed link for legal reasons.

PaidWorker

The Sun the source of all factual information :rolleyes:

Taken from the Article dropped in the bottom as an afterthought

Pace

Flown 12 hours in the affected area, Tue and Wed, and the turbine blades and stators were spotless afterwards. How can zero deposits affect an engine?

Thanks to Sunfish, and Grauniad
 

There has been a lot of ill-considered drivel on this thread.
Thanks to Sunfish for a wise contribution.

I suspect paidworker works for her/his pay in the Belgrano and/or Montreal.

The grauniad mentionned above - here's the link.

Iceland volcano ash cloud: The full story of how the airlines won the battle for the skies | UK news | The Guardian

I normally cannot stand the Grauniad, but for once it appears to have got the story right.

As to the airlines, they have been PATHETIC. If they can't be bothered to give accurate standards to ICAO, then airspace WILL be shut down. There is no point in MOL/WW et al moaning..........it's far too late.......idiots!!

What about the health of the passengers inhaling this stuff?
Are there bleed filters fitted in the Aircon systems that can stop this stuff from damaging your lungs?

I don't think HEPA filters are man enough for the job, if indeed any are fitted at all.

BR.

Not sure about this (last serious physics exposure A levels 1962) but is not the "visibility" of particles dependent on the wavelength of the illuminating beam. Which is why Radar is not seeing some of this stuff. If the particles are the wrong size to be illuminated in the visible light band, we will not see them, just like the radar.

The other issue is gases. The atmosphere is full of molecules that we cannot see. When volcanic sulphur compounds are present (mainly SO2) we cannot see them.
As I recall sulphur embrittlement of turbine blades used to be a serious problem years ago, when fuel content and additive contamination were the source.

No bleed air filters
 

BAD ROBOT,

Contrary to popular belief, bleed air is NOT filtered.

For information on what happens to anyone in an aircraft breathing contaminated bleed air visit Aerotoxic Association - Support for sufferers of Aerotoxic Syndrome

DB :ok:

Agreed. But surely the operators have a responsibility to ensure that they operate within the engine manufacturer's guidelines?

If the manufacturer's existing guidelines are anomalous to the operating situation(s), then operators must surely be obligated to clarify these guidelines with the engine manufacturer BEFORE they put their aircraft up.

CJ

operators must comply with limitations
 

Indeed CJ, the operators must comply with the limitations specified by the manufacturers.

If there is an need to vary, clarify, adjust or disambiguate those limitations then the new acceptable limits must come from the manufacturer.

There's a difference between limitations and recommendations. I don't believe that any manufacturer has published limitations relative to what you must not ingest. They may however published limitations on things like EGT and RPM and part removal times

NASA DC-8 past encounter
 

Podcast

Report

Another user posted the podcast and I posted the report b4 but misteriously they both disappeared. I reckon it must not be against prune's policy to publish those links since a quick search returned many avweb links. Maybe a software bug.