Ash clouds threaten air traffic

[Pace]

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

[breakadjuster]

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!!

[Airbubba]

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.

From Wikipedia:

Shortly after 13:40 UTC (20:40 Jakarta time) above the Indian Ocean, south of Java, the flight crew (consisting of Senior First Officer Roger Greaves and Senior Engineer Officer Barry Townley-Freeman while Captain Eric Moody was in the lavatory) first noted an effect on the windscreen similar to St. Elmo's fire.

British Airways Flight 9 - Wikipedia, the free encyclopedia

[WojtekSz]

Pace:

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.

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.

[peter we]

As others have pointed out, there was obviously a problem with the rules. There is never zero volcanic ash in the atmosphere. We have always coped around the world until an invisible plume hit the UK. Thank heavens we have leaders like Captain Willie Walsh to sort things out.

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.

[Halfnut]

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.

[yoganmahew]

@anotherthing

HMG acted very poorly (well, very seldom) throughout this whole episode

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.

[PaleBlueDot]

WojtekSz, Pace:

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.

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

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.

[visibility3miles]

Sunfish -- Wise advice.

Pace --

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.

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?

[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.

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.

What's the difference between ash and ice

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

[Dairyground]

Some you see, this you don't

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.

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.

[falconer1]

Enginebiz....

The aero engine manufacturers will be the big winners out of this

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...

[Finn47]

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.

[twinboom]

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.

[possibleconsequences]

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?

[visibility3miles]

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.

Quote:
What's the difference between ash and ice

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.

[Low Flier]

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.

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.

[Pace]

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.

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

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

[luoto]

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).

[paidworker]

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.