Ash clouds threaten air traffic

[itsresidualmate]

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]

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. He already answered your question!

Regards,
Sabenaboy

[peter we]

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]

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

BBC News - Up close on Iceland's Eyjafjallajokull volcano

[itsresidualmate]

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]

Originally Posted by itsresidualmate

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]

Fair point BDiONU

[Pace]

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]

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]

let's face it

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]

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]

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]

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]

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

[Pace]

(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]

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]

...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’

Isn't it ironic that I came across that link after reading PBL's blog?

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]

Originally Posted by brooksjg

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]

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

[GarageYears]

Earthquake action continues

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