Why does CASA allow twin engine ETOPS operation at all?
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Dick, I know what you are saying. And it is an interesting question, and provided me with an interesting diversion for an hour or so.
But I don't think that s9A is as all-encompassing as it appears. It talks of a "most important consideration" which I think someone above mentioned does not mean "only consideration".
Also, the legislation should be read as a whole. I think s9A "colours" further sections of the legislation.
Some of the case law talks about
"In reaching this conclusion, the Tribunal is mindful of the requirement in s 9A(1) of the CAA which dictates that a suitably cautious approach must be taken to assessing the risks posed to the safety of air navigation by ..."
and
"However, I am satisfied those provisions merely acknowledge the Parliament's intention that safety of air navigation has always been the principal end to be satisfied by the Civil Aviation Act 1988 and that end has now been expressed in clear words by the Parliament."
And policy that is not contradictory to legislation such as the one I lifted from the CASA website (and I assume there is a policy rather than a webpage) is relevant as well.
"In Re Drake and Minister for Immigration and Ethnic Affairs (No 2) [1979] AATA 179; (1979) 2 ALD 634, Brennan J observed that policy is a key factor in attaining consistency in decision making. Consistency is a desirable goal in administration, as the application of differing standards in the exercise of a power by administrators can only result in unfairness and a consequent lack of confidence in the executive. The AAT should therefore apply lawful policy unless to do so would work an injustice in the particular case or there are other cogent reasons for not doing so (2 ALD at 644-645). A similar view was expressed in Re Ruggeri and Secretary, Department of Social Security (1985) 8 ALD 338 at350. "
So, I would argue that a policy talking about ALARP and s9A are not inconsistent. And if ALARP is OK, then ETOPS should be as well...
But I don't think that s9A is as all-encompassing as it appears. It talks of a "most important consideration" which I think someone above mentioned does not mean "only consideration".
Also, the legislation should be read as a whole. I think s9A "colours" further sections of the legislation.
Some of the case law talks about
"In reaching this conclusion, the Tribunal is mindful of the requirement in s 9A(1) of the CAA which dictates that a suitably cautious approach must be taken to assessing the risks posed to the safety of air navigation by ..."
and
"However, I am satisfied those provisions merely acknowledge the Parliament's intention that safety of air navigation has always been the principal end to be satisfied by the Civil Aviation Act 1988 and that end has now been expressed in clear words by the Parliament."
And policy that is not contradictory to legislation such as the one I lifted from the CASA website (and I assume there is a policy rather than a webpage) is relevant as well.
"In Re Drake and Minister for Immigration and Ethnic Affairs (No 2) [1979] AATA 179; (1979) 2 ALD 634, Brennan J observed that policy is a key factor in attaining consistency in decision making. Consistency is a desirable goal in administration, as the application of differing standards in the exercise of a power by administrators can only result in unfairness and a consequent lack of confidence in the executive. The AAT should therefore apply lawful policy unless to do so would work an injustice in the particular case or there are other cogent reasons for not doing so (2 ALD at 644-645). A similar view was expressed in Re Ruggeri and Secretary, Department of Social Security (1985) 8 ALD 338 at350. "
So, I would argue that a policy talking about ALARP and s9A are not inconsistent. And if ALARP is OK, then ETOPS should be as well...
Come on Dick, you're just being silly now. The whole of aviation runs on probability. Think take off data, airspace & separation, the list goes on.
As I understand ETOPS or EDTO, it's about quantifying risk, bringing it under management.
I'm not sure of your angle in this new near pointless thread but I'm sure it will become clear with a bit more waffle.
Life as a professional aviator is all about probability and managing risk when all is said and done.
As I understand ETOPS or EDTO, it's about quantifying risk, bringing it under management.
I'm not sure of your angle in this new near pointless thread but I'm sure it will become clear with a bit more waffle.
Life as a professional aviator is all about probability and managing risk when all is said and done.
Let us assume that the cost of mitigating a quantified risk to the safety of air navigation is $1. Let us assume that the cost of mitigating a different quantified risk with the same consequences is $10billion. How can CASA choose to mandate the mitigation of one but not the other, when the safety of air navigation is the most important consideration in the decision? In this example the consequences of each risk are the same.
The safety of air navigation demanded that Dominic James not be reinstated to ATPL command privileges. The cost to him was completely irrelevant. Or so CASA said.
I have recently heard a story about an aeronautical engineer who will not fly on the long trans-oceanic routes in anything less than a Boeing 747 or an Airbus A380. This person claims the reason is safety, and that a twin engine airline jet of similar manufacturing date (and therefore safety features) will never be as safe as a four engine aircraft.
He claims the whole ETOPS system is simply based on probability, and that one day, a twin engine aircraft will end up in the drink.
This person claims the safety difference is very small, but it is there nevertheless.
If this is so, how does CASA justify Part 9A of the Civil Aviation Act, which says that the number one priority shall be safety. In this case, it looks as if the number one priority is moving more passengers at a lower cost.
I would like to know what others comments are on this – especially those who have an aeronautical safety qualification and understand the risk matrix.
Presumably if the twin engine planes were as “safe” there would be no reason for ETOPS restrictions.
He claims the whole ETOPS system is simply based on probability, and that one day, a twin engine aircraft will end up in the drink.
This person claims the safety difference is very small, but it is there nevertheless.
If this is so, how does CASA justify Part 9A of the Civil Aviation Act, which says that the number one priority shall be safety. In this case, it looks as if the number one priority is moving more passengers at a lower cost.
I would like to know what others comments are on this – especially those who have an aeronautical safety qualification and understand the risk matrix.
Presumably if the twin engine planes were as “safe” there would be no reason for ETOPS restrictions.
This post tops any other of your loosely based neurotic posts.
Your engineer mate can have any position he likes on which aircraft he wishes to travel but it is no more soundly based than someone else’s view based on religion,politics,skin colour or sexual preference.
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Thread Starter
My whole intention was to show that affordable safety is alive and well.
I can see I have done that.
The act is clearly not complied with as cost is often the driving decision maker.
Sad they have to live a lie!
Lead. You clearly get it. Thanks
I can see I have done that.
The act is clearly not complied with as cost is often the driving decision maker.
Sad they have to live a lie!
Lead. You clearly get it. Thanks
No.
Just because cost is considered, does not mean it is the 'driving' decision maker, just like saying that safety is the most important consideration does not mean that by considering other aspects, safety has taken second place.
I don't necessarily disagree with your view about affordable safety (as I mentioned in my first response), I just don't agree with your argument about the interpretation of the Act.
Just because cost is considered, does not mean it is the 'driving' decision maker, just like saying that safety is the most important consideration does not mean that by considering other aspects, safety has taken second place.
I don't necessarily disagree with your view about affordable safety (as I mentioned in my first response), I just don't agree with your argument about the interpretation of the Act.
Dick, it depends on how you quantify risk.
The premis of your argument in the first post is that 4 engines are safer than 2 and as a consequence casa are not meeting their obligations under the act by not putting safety first.
The basis of this premis is that 4 engines are safer than 2 - is that a fair summation?
I could mount an argument that says the risk of engine fire in a 4 engine aircraft is significantly greater than it is in a twin. It stands to reason that the risk of fire is worthy of consideration and is a significant risk given that the potentially burning engine is located in an area where a fire induced structural failure would be catastrophic. Add to that the fact that the burning engine is directly underneath a fuel tank and the potential is there for the world to come apart. Additionally extra engines increases the risk of an engine failure. It stands to reason that the more engines you have the greater chance you have of one of them giving up the ghost at an inopportune time.
On the basis that most aeroplanes have two or three hydraulic systems, a bunch of electrical systems, a pressurisation system and a couple of redundant controllers, and mostly replicated and redundant systems, regardless of whether they have 2, 3 or 4 engines, there is a strong case that says the more engines you have the riskier it is, so casa may well not be complying with their safety first obligations by banning etops and mandating 4 engine aircraft.
So how is your question answered? Well with the use of probabilities and risk assessments that determine that, on balance, the risk is acceptable given a number of mitigators are in place - these mitigators being the rules around etops/edto.
As for your mate -well he is a dill.
Does he advocate the use of a man with a flag to walk in front of motor vehicles or fit passengers with parachutes or simply ban air travel in its entirety as that would be the safest course of action and without doubt meet CASA’s obligations under the act.
The premis of your argument in the first post is that 4 engines are safer than 2 and as a consequence casa are not meeting their obligations under the act by not putting safety first.
The basis of this premis is that 4 engines are safer than 2 - is that a fair summation?
I could mount an argument that says the risk of engine fire in a 4 engine aircraft is significantly greater than it is in a twin. It stands to reason that the risk of fire is worthy of consideration and is a significant risk given that the potentially burning engine is located in an area where a fire induced structural failure would be catastrophic. Add to that the fact that the burning engine is directly underneath a fuel tank and the potential is there for the world to come apart. Additionally extra engines increases the risk of an engine failure. It stands to reason that the more engines you have the greater chance you have of one of them giving up the ghost at an inopportune time.
On the basis that most aeroplanes have two or three hydraulic systems, a bunch of electrical systems, a pressurisation system and a couple of redundant controllers, and mostly replicated and redundant systems, regardless of whether they have 2, 3 or 4 engines, there is a strong case that says the more engines you have the riskier it is, so casa may well not be complying with their safety first obligations by banning etops and mandating 4 engine aircraft.
So how is your question answered? Well with the use of probabilities and risk assessments that determine that, on balance, the risk is acceptable given a number of mitigators are in place - these mitigators being the rules around etops/edto.
As for your mate -well he is a dill.
Does he advocate the use of a man with a flag to walk in front of motor vehicles or fit passengers with parachutes or simply ban air travel in its entirety as that would be the safest course of action and without doubt meet CASA’s obligations under the act.
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I am just a pax: a pax who sat at 35,000'+, in the middle of the night, over the middle of the Pacific, in a 777 for the first time, and consciously re-examined my faith in the ETOPS calculations.
The question sounds a bit bush-lawery. That is, there is surely no longer any serious question about the practical safety of ETOPS, so the question is about the wording of the legislation. That is a question about legal interpretation, not aviation safety.
I am no more a lawyer than an aviation professional, but from a common sense point of view, it would seem that the law would be complied with if the reasoning went like this:
-We want to operate twins over the Pacific, because cheaper.
-We see your point, but our principal objective is safety. Demonstrate that you can do this as safely as flying the Queen of the Skies.
-Engines have got a lot more reliable. Here is a metric merde-tonne of calculations and a set of regulations, beyond what is considered safe for normal twin operations, that support our point.
-You have persuaded us that your calculations are sound, and there will be no diminution of safety, so you may do this, unless/until experience shows we got something wrong.
Experience would seem to indicate that the result has been no diminution of safety. The last time I had an aeroplane on my avoid list, it had nothing to do with the number of engines, and everything to do with the type of batteries.
Meanwhile, the corporate culture of profit-maximization as the first priority (in all airlines) has me more worried than the number of engines.
The question sounds a bit bush-lawery. That is, there is surely no longer any serious question about the practical safety of ETOPS, so the question is about the wording of the legislation. That is a question about legal interpretation, not aviation safety.
I am no more a lawyer than an aviation professional, but from a common sense point of view, it would seem that the law would be complied with if the reasoning went like this:
-We want to operate twins over the Pacific, because cheaper.
-We see your point, but our principal objective is safety. Demonstrate that you can do this as safely as flying the Queen of the Skies.
-Engines have got a lot more reliable. Here is a metric merde-tonne of calculations and a set of regulations, beyond what is considered safe for normal twin operations, that support our point.
-You have persuaded us that your calculations are sound, and there will be no diminution of safety, so you may do this, unless/until experience shows we got something wrong.
Experience would seem to indicate that the result has been no diminution of safety. The last time I had an aeroplane on my avoid list, it had nothing to do with the number of engines, and everything to do with the type of batteries.
Meanwhile, the corporate culture of profit-maximization as the first priority (in all airlines) has me more worried than the number of engines.
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SPECIOUS ARGUMENTS.
('MY WORD' Is a word game, played by people whose business is words.)
In what circumstances can CASA say that saving the costs of mitigating a risk to the safety of air navigation is more important that mitigating the risk?
Did someone just say "dill" ? (whose self-editing is far from flawless.)
Why do the drafters of all these rules and regs use such appalling
terms as "appetite", presumably trying to colour the terminology as to whether or not the regulator is hungry for getting "the matrix" just right, on his plate.
But all that, and all that, is merely muttering in the wings.
('MY WORD' Is a word game, played by people whose business is words.)
In what circumstances can CASA say that saving the costs of mitigating a risk to the safety of air navigation is more important that mitigating the risk?
Did someone just say "dill" ? (whose self-editing is far from flawless.)
Why do the drafters of all these rules and regs use such appalling
terms as "appetite", presumably trying to colour the terminology as to whether or not the regulator is hungry for getting "the matrix" just right, on his plate.
But all that, and all that, is merely muttering in the wings.
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However, considering the circumstances which caused the engine flame-outs a trimotor or 4 engined aircraft may have lost all.
The answer Dick is a question of probabilities. If one reviews the total components of an aircraft most are covered by MTBO (mean time between overhauls and/or MTBF (mean time between failure) determining when such component should be removed for inspection/overhaul or replacement.
Similarly ETOPS is based upon MTBAEF (mean time between all engine failure) predicated on statistical and operational data where the Actuaries consider and define probabilities which the Regulator makes the decision upon.
The total industry is based upon probabilities yet in 2017 we had a year without any airline fatalities.
The answer Dick is a question of probabilities. If one reviews the total components of an aircraft most are covered by MTBO (mean time between overhauls and/or MTBF (mean time between failure) determining when such component should be removed for inspection/overhaul or replacement.
Similarly ETOPS is based upon MTBAEF (mean time between all engine failure) predicated on statistical and operational data where the Actuaries consider and define probabilities which the Regulator makes the decision upon.
The total industry is based upon probabilities yet in 2017 we had a year without any airline fatalities.
2017 safest year for air travel as fatalities fall - BBC News
I don't recollect any DC3 ending up in the water when NAC operated the Coral Route.
Thread Starter
Every Australian country town that has a FAR23 certified scheduled service rather than a FAR25 shows that CASA has put affordability as the more important consideration.
They are then clearly not putting safety as the most important consideration.
Pretty simple. I am not opposed to this.
They are then clearly not putting safety as the most important consideration.
Pretty simple. I am not opposed to this.
Moderator
A four-engined jet could end up in the drink one day, too. B747 + Mount Pinatubo = quadruple engine failure.
A four-engined jet could end up in the drink one day, too. B747 + Mount Galunggung (Indonesia) = quadruple engine failure.
I understand a Manila based TNT owned Bae146 freighter operating Singapore to Manila entered volcanic ash from Pinatubo and came within 2,000 feet of ending up in the South China Sea, before they got some of the Lycoming ALF 502's turning and burning again.
I stand corrected - Mount Galunggung, not Mount Pinatubo. Back to the topic...
The reality is that affordable safety is everywhere, and is unavoidably everywhere.
The problem in aviation regulation - particularly in Australia - is that the estimation of the probabilities of things happening - like a double engine failure on a 777 or an engine failure in a C208 or PC12 - are almost invariably grossly overestimated. The required mitigations are, accordingly, almost invariably a gross overreaction. It’s across the regulatory spectrum, from air operator certification to medical certification. The proposal for 20nm CTAF procedures is a specific, recent example.
The reason for this is completely uncontroversial and well-understood. The contemplation of awful consequences - like a double engine failure in a twin jet at 35,000’ over the ocean or a mid-air near a CTAF - results in a natural overestimation of the probabilities of it happening.
Dick’s aeronautical engineer - if he exists - is merely being what’s known as ‘human’. He intuitively ‘knows’ that a four engined-aircraft ‘must’ be safer than a two engined-aircraft. His knowledge and experience and objectivity go out the figurative window when he intuitively ‘knows’ the comparative risks.
‘Everyone’ intuitively ‘knows’ that pilots with CVD ‘must’ not be able to meet the same competence standards as pilots without CVD, and therefore pilots without CVD ‘must’ be riskier than pilots without CVD.
Of course, as a matter of objective fact, the intuition is bollocks. But it is natural (and, purely coincidentally, very lucrative for those who make their living out of safety bureaucracy).
Manifestations of this are everywhere. Look at the component overhaul and replacement periodicities in most GA aircraft designed in the 50s/60s/70s. My favourite is the flap flex drive shafts on Beechcraft. There are aircraft with 10,000 hours, plus, flying around with the original shafts. There are thousands of aircraft with multiple thousands of hours on original shafts. What do you reckon the maintenance manual says about the ‘life’ of those shafts?
And then I think of the poor bastard LAME whom CASA crushed for not having replaced vacuum pumps on a Cessna 310 at 500 hours. The pumps were still going strong after 500 hours, one by a further 886.9 hours and the other by a further 1,599.6 hours. But he had to be crushed because someone had plucked 500 out of his arse to put in a maintenance manual 40 years ago, and the number thus became holy writ the breach of which was a safety heresy. The objective evidence of millions of hours of vacuum pump operation and the collective wisdom of what causes vacuum pump failure were irrelevant. That’s aviation ‘safety’ for ya...
The reality is that affordable safety is everywhere, and is unavoidably everywhere.
The problem in aviation regulation - particularly in Australia - is that the estimation of the probabilities of things happening - like a double engine failure on a 777 or an engine failure in a C208 or PC12 - are almost invariably grossly overestimated. The required mitigations are, accordingly, almost invariably a gross overreaction. It’s across the regulatory spectrum, from air operator certification to medical certification. The proposal for 20nm CTAF procedures is a specific, recent example.
The reason for this is completely uncontroversial and well-understood. The contemplation of awful consequences - like a double engine failure in a twin jet at 35,000’ over the ocean or a mid-air near a CTAF - results in a natural overestimation of the probabilities of it happening.
Dick’s aeronautical engineer - if he exists - is merely being what’s known as ‘human’. He intuitively ‘knows’ that a four engined-aircraft ‘must’ be safer than a two engined-aircraft. His knowledge and experience and objectivity go out the figurative window when he intuitively ‘knows’ the comparative risks.
‘Everyone’ intuitively ‘knows’ that pilots with CVD ‘must’ not be able to meet the same competence standards as pilots without CVD, and therefore pilots without CVD ‘must’ be riskier than pilots without CVD.
Of course, as a matter of objective fact, the intuition is bollocks. But it is natural (and, purely coincidentally, very lucrative for those who make their living out of safety bureaucracy).
Manifestations of this are everywhere. Look at the component overhaul and replacement periodicities in most GA aircraft designed in the 50s/60s/70s. My favourite is the flap flex drive shafts on Beechcraft. There are aircraft with 10,000 hours, plus, flying around with the original shafts. There are thousands of aircraft with multiple thousands of hours on original shafts. What do you reckon the maintenance manual says about the ‘life’ of those shafts?
And then I think of the poor bastard LAME whom CASA crushed for not having replaced vacuum pumps on a Cessna 310 at 500 hours. The pumps were still going strong after 500 hours, one by a further 886.9 hours and the other by a further 1,599.6 hours. But he had to be crushed because someone had plucked 500 out of his arse to put in a maintenance manual 40 years ago, and the number thus became holy writ the breach of which was a safety heresy. The objective evidence of millions of hours of vacuum pump operation and the collective wisdom of what causes vacuum pump failure were irrelevant. That’s aviation ‘safety’ for ya...
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JMHO:
I don't think there is any question that any safety must be affordable safety - the only alternative is an outright ban. What I mean is, you can always make something "safer", by spending more or doing more. You have to draw a practical line somewhere.
We could have the passengers wearing crash helmets and fire-proof suits. That would have saved some lives over the years. We could be building aircraft components out of more expensive materials, and replacing them more often.
CASA needs to decide the rules, using safety as the most important consideration, but that doesn't mean "utmost safety", because that simply doesn't exist.
It needs to be acceptably safe (and in aviation that means a very low risk: no-where near the risks we accept in other areas of life, such as motor vehicles).
So of course CASA is invested in affordable safety, even if they don't use that phrase. If they weren't, they'd have to ban aviation in it's entirety.
But, Dick, using ETOPS (or EDTO as it now is, which also affects 4-engined aircraft) is probably not a good test case if you're mounting an argument to take up the tree. I'm sure you can find a better one.
As for CASA coming down to hard on GA etc, the problem is they keep crashing and killing themselves. The airlines aren't. So CASA have to be seen to be doing something about it. I think that problem actually goes further up the tree than CASA, it's the whole "nanny state" culture that Australia seems to have evolved into, from the top down. I don't know why, it just has. I wish I knew how to fix it.
I don't think there is any question that any safety must be affordable safety - the only alternative is an outright ban. What I mean is, you can always make something "safer", by spending more or doing more. You have to draw a practical line somewhere.
We could have the passengers wearing crash helmets and fire-proof suits. That would have saved some lives over the years. We could be building aircraft components out of more expensive materials, and replacing them more often.
CASA needs to decide the rules, using safety as the most important consideration, but that doesn't mean "utmost safety", because that simply doesn't exist.
It needs to be acceptably safe (and in aviation that means a very low risk: no-where near the risks we accept in other areas of life, such as motor vehicles).
So of course CASA is invested in affordable safety, even if they don't use that phrase. If they weren't, they'd have to ban aviation in it's entirety.
But, Dick, using ETOPS (or EDTO as it now is, which also affects 4-engined aircraft) is probably not a good test case if you're mounting an argument to take up the tree. I'm sure you can find a better one.
As for CASA coming down to hard on GA etc, the problem is they keep crashing and killing themselves. The airlines aren't. So CASA have to be seen to be doing something about it. I think that problem actually goes further up the tree than CASA, it's the whole "nanny state" culture that Australia seems to have evolved into, from the top down. I don't know why, it just has. I wish I knew how to fix it.
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D.S. is peeved. The bureaucrats are lying to him. (Is that such a revelation?)
He has his sympathisers and he has his detractors, obviously. (Did not even Jean Jacques Rousseau endure this, in his "brave new world"?
And do they not , too have their incidental place, those who are so world-weary, as to say, "go away"?
He has his sympathisers and he has his detractors, obviously. (Did not even Jean Jacques Rousseau endure this, in his "brave new world"?
And do they not , too have their incidental place, those who are so world-weary, as to say, "go away"?
...those who are so world-weary, as to say, "go away"...
It's not necessarily "world-weary" but SMITH weary although weary is grossly understating things...
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Does that count?
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Over 50 years in aviation and 12500 hrs worldwide.
Engine Shutdowns
2 Engines nil
3 Engines 1
4 Engines 2
Based on my experience I would say that twin engine aircraft are very reliable, engine wise.
SRM
Engine Shutdowns
2 Engines nil
3 Engines 1
4 Engines 2
Based on my experience I would say that twin engine aircraft are very reliable, engine wise.
SRM