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Why did Air France 447 go down?


cp fa

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Didn't a Westjet pilot find himself compelled to climb a few thousand feet above the 737's service ceiling to avoid an overspeed a few years ago? In my experience pulling off some power slows the aircraft almost as fast as climbing it and this has always been enough to keep me from an overspeed due to changing winds at cruise altitude. Maybe I just haven't flown in the same conditions but I find it hard to imagine a wind change that is so abrupt that it requires a 2000' climb to avoid overspeeding (but just because it hasn't happened to me doesn't mean it can't happen!).

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I've had it happen in the A320, and it was quite surprising. We were northbound at FL350 near Nassau, flying in clear air. There was a line of heavy thunderstorms over Florida, about 40 miles inland of the east coast, so a good 90 to 100 miles away from us. An airplane 5 minutes in front of us reported moderate turbulence, so we had everyone seated. When we encountered it, the wind speed increased very rapidly, something in the order of 50 or 60 kts with a significant veer to the northwest. I went to idle and we were still accelerating rapidly. I had to climb about 1500 ft, even then we still oversped enough that an inspection was required on arrival. All in all, not a pleasant experience.

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I have never encountered such a situation or been trained on it. I am wondering if if might just be best to not climb and just reduce thrust and if there is a bit of an overspeed, then so be it as it might be less risky than doing some sort of climb manouver at high altitude. Apparently some aircraft can have different handling characteristics at high altitude in that they are much more pitch sensitive. A brick wall is not going to be hit we are temporarily mach .02 over the limit.

Any thoughts.

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I have never encountered such a situation or been trained on it. I am wondering if if might just be best to not climb and just reduce thrust and if there is a bit of an overspeed, then so be it as it might be less risky than doing some sort of climb manouver at high altitude. Apparently some aircraft can have different handling characteristics at high altitude in that they are much more pitch sensitive. A brick wall is not going to be hit we are temporarily mach .02 over the limit.

Any thoughts.

It sounds to me like the recovery from the impending overspeed was essentially correct but it was the recovery from the recovery that was mishandled.

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"It sounds to me like the recovery from the impending overspeed was essentially correct but it was the recovery from the recovery that was mishandled."

This WAS NOT an accident! The causes are fairly straight forward; the occupants of the flight deck were not appropriate to the 'task', period!

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Defcon,

I think that the causes - and that's 'plural' btw - are far more complex than simply blaming it on the "occupants of the flight deck". The following is a letter posted on AVweb; quite thought provoking imho..

Airbuses Fly "Like a Video Game"

I would like to offer my comments and perspective with regard to the Air France Flight 447 accident. I have been a A-330 captain since 2003 and have over 4500 hours in the aircraft. While many A-320 pilots undoubtedly have more series time, I believe this probably makes me one of the most experienced A330 pilots in the world.

When asked how I like the aircraft, I tell people that there is likely no easier airplane to take over an ocean, and that the systems design and presentation is superb. That said, the automation is more complex and less intuitive than necessary, and the pilot-aircraft interface is unlike that of a conventional aircraft. Most important with regard to this accident is the fly-by-wire sidestick control. The sidestick itself has a very limited range of motion, making inadvertent over-control very easy. Of even greater significance, the stick itself provides no "feel" feedback to the pilot. That is, unlike a conventional aircraft, the pilot does not get a sense through pressure of how much input is being sent to the control surfaces. The most important advice I give to pilots new to the Airbus is to treat the aircraft not as an airplane, but as a video game. If you wait for the sidestick to tell you what you are doing, you will never get an answer.

Taking into consideration that Air France 447 was at FL 350 (where the safe speed envelope is relatively narrow), that they were in the weather at night with no visible horizon, and that they were likely experiencing at least moderate turbulence, it does not surprise me in the least that the pilots lost control of the aircraft shortly after the autopilot and autothrust disconnected.

Let's keep in mind that these are not ideal conditions for maintaining controlled flight manually, especially when faced with a sudden onslaught of warning messages, loss of autofllght, confusing airspeed indications, and reversion to "alternate law" flight control, in which certain flight envelope protections are lost.

A very bad Airbus design feature is thrust levers that do not move while in autothrust. They are instead set in a detent which would equal climb trust in manual mode. If the pilots did not reset the thrust levers to equal the last cruise power setting, they likely eventually ended up in climb power, making it difficult to reset the proper cruise power setting and adding to what was likely already a great deal of confusion.

But the real problem probably occurred immediately after the pilot flying grabbed the sidestick and took over manually. Unfortunately, airline pilots rarely practice hand-flying at high altitude, and almost never do so without autothrust engaged. As a result, we forget that the aircraft is very sensitive to control inputs at high altitude, and overcontrol is the usual result. Because the Airbus sidestick provides no feedback "feel" to the pilot, this problem is dramatically compounded in this aircraft.

I believe the Air France pilot grabbed the sidestick, made an immediate input (because as pilots, that's what we tend to do), and quickly became quite confused as to what the aircraft was truly doing. This confusion likely was exacerbated by fixating on airspeed indications that made no sense while trying to find a power setting with no airspeed guidance.

When transitioning from autopilot to manual control at altitude in the Airbus, the most important thing to do at first is nothing. Don't move a thing, and then when you do, gently take hold of the sidestick and make very small inputs, concentrating on the flight director (which, in altitude hold, should still have been providing good guidance). Of course, this is much easier said than done with bells and whistles going off all over the place, moderate turbulence and a bunch of thunderstorms in the area. As I said before, treat it like a video game.

So why did the Air France pilot find himself at the limits of sidestick travel, and then just stay there, maintaining a control input that simply could not logically be correct? When things go really bad and we are under intense pressure, it is human nature to revert to what we know from previous experience. Remember, the Airbus flies like no other aircraft in that the sidestick provides no feedback to the pilot. It is a video game, not an airplane.

I believe the Air France pilot unintentionally fell back on all of his previous flying experience, in which aircraft controls "talkedF" to him when he moved them. Distracted by many confusing inputs, he instinctively expected to be able to control the aircraft by "feel" while dividing his attention to address other matters. I've seen it happen in the simulator, and in an Airbus this is a sure way to lose control of the aircraft and is possibly the most dangerous aspect of Airbus design philosophy.

One last note: Airbus pilots often claim that the aircraft "can not be stalled." When the flight controls are in "normal law" this is a reasonably true statement. However, in "alternate law," as was the case here, stall protection can be lost. If we ever practiced this in the simulator, I don't remember it.

Lest anyone think I am blaming the Air France pilots for this accident, let me be clear. Despite all of my experience in the aircraft, I am not the least bit certain that I would have been able to maintain control under the same circumstances. I do feel certain that were you to spring this scenario on pilots in a simulator without warning less than half of them would have a successful outcome. Safely flying the 320, 330 and 340-series Airbus requires something of a non-pilot mindset.

Name Withheld

Editor's Note:

We have spoken with the writer of this letter to confirm his identity and honored his request for anonymity.

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It sounds to me like the recovery from the impending overspeed was essentially correct but it was the recovery from the recovery that was mishandled.

I'm not clear about which aspects of that recovery would be "correct". Probably like most of us, I haven't seen the scenario in the sim', but again probably like most, I have seen some pretty good airspeed increases. Nothing quite as dramatic as Jeff's tho'. Thrust reduction is obviously a first response, and an intuitive one, but if that's not doing the trick, would not an application of speed-breaks be preferable to an uncleared climb? No criticism implied, just wondering why nobody's brought it up, in what's now a pretty lengthy discussion.

.... I think that the causes - and that's 'plural' btw - are far more complex than simply blaming it on the "occupants of the flight deck". The following is a letter posted on AVweb; quite thought provoking imho..

Thanks for the post, bluemic. There seems to be, here and in the EK@DME thread, an unseemly rush to denigrate the crews. Plenty of room for questions (in both cases), but I can't help thinking that the tone on both threads might be a little different if they'd worn different uniforms :whistling:

Cheers, IFG :b:

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Thanks for your thoughts bluemic.

I have attempted to qualify my 'opinion' on the available data as, 'premature'. I also admit; I am adversely sensitive to matters relating to 'crew qualification & standards’.

Airbus may be producing aircraft from technologies which do and will require 'new operational thinking' going forward on the part of pilots and perhaps, maintenance as well. Maturing operations have identified a number of operational deficiencies to date, which is an expected and 'normal' part of the process. Not being 'Airbus' qualified; I have avoided making any comment respecting Airbus design 'philosophy'.

Opposite, I do know something about piloting and remain of the opinion; the AF 447 event was not an accident. The available information is quite clear, no one was in 'command' of AF 447, nor likely even remotely qualified for same, which quickly lead to poor decisions and an equally expedient loss of control. This situation is in fact one which is likely to be repeated as industry growth attempts to make qualified pilots out of people that should be cutting their teeth on aircraft such as the Aztec etc, not large commercial aircraft.

A week or so ago, mainstream media was asking the question; ‘has the technology of automation resulted in pilots forgetting how to fly’? Personally, I thought the question fell considerably short. The media should also be asking; ‘where did or will the ‘graduates’ of global air cadet programs ever get ‘ANY’ real flying experience’?

No political interference intended, but in the pure interest of safety, I believe we’ve got to keep ‘experience’ in the air as long as may be medically possible while issues revolving around collective agreements and other legislation are placed ‘second’ in importance.

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Welcome to the future.

The benefits of being either a pilot or an AME for the majority of those seriously considering the profession is not worth the initial investment and the long term apprenticeship. That is why they will turn to these so called cadet programs as the only alternative I have no optimism for a positive outcome. As far as piloting is concerned it is an easy job 99% of the time. Pilots are paid for that other 1% and the ability to deal with that 1% comes from comprehensive training and experience.

Greg

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Welcome to the future.

The benefits of being either a pilot or an AME for the majority of those seriously considering the profession is not worth the initial investment and the long term apprenticeship. That is why they will turn to these so called cadet programs as the only alternative I have no optimism for a positive outcome. As far as piloting is concerned it is an easy job 99% of the time. Pilots are paid for that other 1% and the ability to deal with that 1% comes from comprehensive training and experience.

Greg

Greg;

...and corporations such as airlines have demonstrated over and over again that they are willing to bet on that 1% and charge up the accident and fatalities to the cost of doing business more cheaply...at least that is the way it seems whenever the question of how things are actually done is examined. Shareholder and profit are increasingly privileged over the principles of aviation, but only pilots have recognized this in the past and have spoken out. It is now finally, in the wake of several inexplicable, major fatal accidents becoming an open question.

The character of aviation accidents is changing and is tragically proving this point. Otherwise, how do we explain why flight crews, understood as "highly skilled" continue to violate the first principle of aviation and stall their aircraft?...the count is at least a dozen so far in the last five years.

Nor am I optimistic, because the principles of business are trumping the principles of aviation in a mistaken notion that cheaper/faster is better.

But the question is not one of optimism or pessimism; it is rather a question of trying to prevent the next accident by bluntly confronting some inalienable facts concerning the flying of airplanes and keeping people alive and keeping a commercial aviation enterprise viable and rewarding for the shareholders.

Flying an airplane is a cognitive skill of which not everyone is capable, nor is everyone equipped to do, safely. Yet the infatuation with the economics of automation prohibits or at least intervenes in this critical understanding of flight. Those managing the hiring, training and standards of commercial aviation enterprises must have the courage to run against popular thinking and begin to examine the real cost of hiring and paying cheaply. As I said a dozen years ago when these trends were beginning, those with the intelligence, native ability, personal discipline, keenness and willingness to stick out an atrocious apprenticeship at atrocious wages just for a chance to fly for the "majors", (if that's what one can call airlines today), will seek, and now are seeking professions elsewhere, where respect, reasonable earnings, a reasonable expectation of a secure retirement and some reward for the enormous cost of buying entry into the profession may be expected. Aviation has always been a tough mistress but compared to when you and I and our contemporaries flew and enjoyed our career, today's "profession" has been desecrated in order to down-guage wages, expectations and secure futures, and the notion that "these airplanes fly themselves, and therefore less experience, less skill, and less remuneration" is justified by those who don't, (and can't) fly.

AF447 was not an "automation accident". It was a cognitive accident in which the three crew members could not determine if their aircraft was stalled despite the 15,000fpm rate of descent against a 15deg NU pitch attitude. Instantly pulling 2/3rds back stick in response to a loss of airspeed indication is a complete and utter mystery, but, short of bluntly comparing the incorrect control response to the Colgan Q400 accident at Buffalo, sustaining such back stick and pitch attitude during subsequent auditory and visual stall indications takes this accident out of mere competency explanations and into fundamental cognitive explanations. Those who specialize in human factors are finally catching up to those who fly these automated aircraft and recognizing that these issues do not just require "more training". We saw this fifteen years ago, but it is economics, not automation, which is the challenge.

As pilots who have to fight this battle, we are constantly told to "accept what the market will bear". Well, quite frankly to hell with the market and that ignorant statement if the result is the kind of accidents we are seeing today. Such an attitude is intolerable and strange in the face of such trends. It is not a mere balancing act between profit and safety - both can be done but there must be no illusions as to the value of experienced, well-trained and highly-skilled airline pilots. As you say Greg, the "cadet" program is a questionable response to the expense of hiring and training. The MCPL is a lousy licensing process which puts 250-hour, rote-trained wonders who are completely inexperienced into the right seats of Boeings and Airbuses, leaving the captain on his or her own when that 1% moment strikes. It reeks of betting the odds by those who don't comprehend the business they're in, as if automation can somehow sort it all out and the "expensive" pilots are just along for the ride.

This is blunt and those who run airline companies won't like it and will see this as impolitic but it is the truth about your business and needs to be said. The principles of aviation...of staying alive and keeping one's passengers alive while making a go of the business demands first that such principles be acknowledged and respected. Blaming pilots will only ensure the continuance of the present trend - the underlying causes are organizational and must be addressed first. For that to happen, private, for-profit enterprises need to acknowledge these facts and, beyond what the FAA requires, (Transport Canada appears to be entirely silent on the matter, (and still does not require approach-to-the-stall training in fly-by-wire aircraft)), reverse the trend which has made a career in aviation so unattractive as a profession while commercial aviation itself has become exponentially more complex and demanding of the human pilot.

Those who think that "pilotless airliners" are just around the corner are living in dreamland, but perhaps even the industry knows at least that. The "1% factor" is trending in exactly the opposite direction for this notion to become a reality anytime soon.

On a more pleasant topic, we're thoroughly enjoying travelling in Italy at the moment. CPFA, blues deville, others...many thanks on that thread for your solid advice. When we return, I hope to offer some more. Been driving here in Tuscany for a week (after a week in Rome and a week in Florence), and it is a pleasure - highways always really twisty (lessee...now where did I put that Porsche?), but well-marked and well-signed. Blues...get an International Driver's License...about $CAD15. We travelled to San Argentario yesterday and for the second time, swam in the warm Mediterranean - visited Castello di Brolio (http://www.ricasoli.it/), to find some fine Chianti...highly recommended. Off to Venice next week.

Don

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HI Don

Everything that you said in that post is absolutely true. The problem is that for any airline to recognize the problem and start to pay skilled employees a better wage and pay more for training is difficult. Passengers, (or for those who prefer it guests :) ) go on the computer and buy the lowest priced fare. Practically speaking airlines have to cut back wherever they can. This goes against my political ideology but it seems to me that we are going to need some form of regulation to solve the problem which will be difficult because it would require international co-operation. Another issue is that unions are going to have find a way to give the airline greater ability to release someone is can't maintain a reasonable standard. Like you said not everyone is cut out for the job.

As far as our airline is concerned I'll go back to what I suggested before. I think that the first right seat position and the first left seat position for every pilot at AC should be on the Embraer. They would at least get experience that they'll never get flying 12 to 15 hour legs across oceans. All JMHO.

Again Don that was a great post. Glad you enjoyed Italy.

Greg

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Hi Greg;

The neoliberal concept of economics, (free markets, de-regulation of financial institutions, privatization of formerly public and/or government organizations, dismantling of the Keynesian Welfare State so ordinary people must fend for themselves, all of which favour private tyrannies known as "corporations", ("tyrannies" because corporations are at once more powerful than many governments but are unelected and legally secretive while controlling the social life of countries), is responsible for the race-to-the-bottom in terms of airline fares, (and a host of thousands of other such changes since the early '70's, when Bretton-Woods was dismantled by the US under President Nixon), which of course flies in the face of many of the principles of aviation.

But that is too black-and-white an assessment of course...monopolies have their own brand of 'tyranny' which neoliberalism promised to eradicate. Airlines have consistently charged less than it costs them to sustain a viable operation and this was before de-regulation in the eighties. The relative success of even the legacy carriers has proven that both costs and fares were too high. A de-regulated industry had to adjust as all others had too, to a more laissez-faire economic environment. I frankly think that was a healthy move but like all things , but that was before two recent (late 1800's) financial notions emerged from the shadows and emerged to displace government in the running countries and the social lives of the populations residing therein. These two notions were the "corporation" and the "speculative economy".

During the Industrial Revolution, (which began in Shropshire, more specifically Shrewsbury, where Charles Darwin was born and lived), the notion of the "corporation" was created, and was quickly granted the same status as a citizen of the country of residence along with a new concept, "legal longevity" which provided unlimited lifetime for the entity. The notion of a 'speculative economy" came later in the 19th Century and developed rapidly at the beginning of the 20th Century. Speculation - the activity of formal betting on a corporation's shares in a secretive environment which favours inside knowledge justified by the illusion that this was "investing", slowly displaced an economy in which making things - manufacturing - an economic activity upon which all countries economies had been solely based. Speculation's hand-maiden - a boom-bust cyclic economy which favours the few who, by design and eventually by law, "run the house", provided the necessary means by which untold wealth may be captured both on the way up and on the way down.

Like the notion of "managing" something, the activity of speculation never directly produces anything of value - it is justified under the notions of raw capitalism as a means of appropriating as much capital in one place as may be amassed and reinvesting it in the capital machine. Capitalism isn't a social system which intends to look after ordinary people, it is a system of wealth accumulation justified for the longest time by institutionalized (vice one's privately-held) religion. Max Weber's, "Protestantism and the Spirit of Capitalism" is an early examination of this social justification for eliminating social principles. There are many other works even today, which examine the complex relationship between wealth and religious belief systems.

By the time WWII had been lost and won, the war-machine, including the populations returning from warmacht, had to be given new goals and tasks. For a while, the Keynesian Welfare State, as it came to be known, flourished and ordinary people could expect a washing machine in every laundry room, so to speak. But the profits brought by war diminished and the KWS interfered with post-war profits. The US dollar began to lose value and in 1971 the United States took the dollar off the gold standard to free it up on the open (speculative) market by dismantling the Bretton-Woods agreement (created if I recall in 1941).

Corporations were slowly freed of the shackles of regulation under what came to be known as a "neoliberal" economy, first openly championed by the Reagan-Thatcher duo. The intent was to return private enterprise to massive profits while dismantling the KWS. The "success" of this single U.S. initiative is, I'm sure, beyond the wildest dreams of those who in the early 70's, seriously considered the idea beneficial to their personal gain and therefore to "the excess population"...so to speak. The notion of "trickle-down" was created to sooth such population, and diversions such as sports, consumer shopping, entertainment and other "light" activities which accomplish little, became all-American institutions which kept the population occupied while the US government continued to invade-but-not-occupy other countries for the resources necessary to keep their increasingly speculative economy thriving.

Gradually, laws changed to enhance the protection of corporations and the notion of "private profit, socialized risk" was created so that when private enterprise failed, it was up to governments to "prevent economic damage" by bailing out the failures with public money. The US banks are a prime example and we know the other examples. In a de-regulated economy, there are only private rules which are beyond the view and therefore inspection of the population at large.

As a way of enhancing profit for increasingly greedy speculators, euphemistically known as "investors", the "We'll leave if you don't reduce corporate taxes" ploy became a powerful threat to increasingly intimidated, compliant (left and right) governments who would see their country's economy out-sourced to cheaper labour markets - an astonishingly clear example of short-term thinking.

So...in this mix, airlines had to do something and because the capital investments are huge, the money had to come from the only "flexible" source remaining: employees (career degradation), and future employees, (B-scale wages) and retired employees, (destroyed pensions). The cycle is, of course, vicious - as wages go down, people cannot afford to buy things even if they are made overseas by cheap labour. People cannot buy "expensive" airline tickets because they're trying to house, feed, cloth and educate their families first, so prices have to come down.

But the principles of aviation do not change. Feynman was famous for many sayings and his comment that politics cannot fool nature is entirely appropriate here - Aviation is far too cheap today and the sense of entitlement to yet-cheaper fares is itself an institution with which the airlines must wrestle. At some point such a system, already under stress, must show signs of failing. And it is.

Arctic Ace:

I agree with your comment and was up front for most ITCZ crossings on the Pacific, but the weather that night was not especially unusual - they experienced nothing more than light turbulence during the entire time, except just after the first stall during the initial 7000fpm pitchup. This flight was in every respect nominal, until the pitch-up. It was recoverable up to just past the apogee; it was irrecoverable after the descent from the apogee began. The pitch attitude was 16deg and the angle-of-attack was >40deg until impact.

Don

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Don Hudson For Prime Minister :icon_super:

Hey Don,,,

There's an opening for top job with the NDP. I think you would be an ideal replacement for Jack :Clap-Hands:

Iceman

I would rather ordinary people get sufficiently aware and when they know how things are, sufficiently angry to confront private tyrannies to take just a little back of what was theirs, and what was their country. I think the notion of "leadership" should ebb and flow between that and "follower-ship" - people should be able to think for themselves rather than just accepting what others say or think. I would prefer a cantankerous society that watches what it's leaders are doing, but today that simply isn't possible because people are intellectually lazy and physically and emotionally satiated with the elixirs I mention above. The work of awareness and change is way too hard, until one day it impinges and perhaps even limits one's personal sense of entitlement to this or that.

The kind of economy we have, the kind of social structure we have, is one which we have permitted and with which we have been complicitous - we have tacitly given permission to our leaders to do this "in our name", without a whisper of protest or hint of revolution. Jack was an enormously popular leader and justifiably so but in my view we should not require the services of "the NDP" or even a leader...we should be relying upon the intelligence of ordinary people to enact real change. Otherwise those responsible for the current state of affairs will remain in charge. Change is a very tall order when we're all working our asses off just to get by. Change is a very tall order for a society literally drunk on excess - a situation which the very rich reinforce and sustain through legal and other means. I've been in politics once, and that was enough.

I would just like to see this kind of dialogue start up in all those places ordinary people inhabit. I would like the power exerted over our society by business to literally become visible, because right now we think all this is normal and it isn't. It is dysfunctional, except for the very wealthy few, and our government, regardless of who is in power. It is not "business" that is bad - it is the use of power which large corporations wield over our society, without representation, without election and without end, that is the problem. The airline issue is a tiny part of that phenomenon.

Don

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Hi Don

You make some good points but the thing is IMHO that what actually matters more than ideology is character. I sit on the conservative side of things but I'd rather have someone on the left with character in power, than a conservative without.

I think that both sides have their problems but I think that we are very heavy in bureaucracy with no discernable way out. For years I've advocated consolidating various social programs. My favoured vehicle would be a "guaranteed annual income". However there are too many bureaucratic oxes to be gored to have that ever see the light of day. We had a chance in this province to actual remove a whole tax bureaucracy and because Campbell so badly managed the politics of it we are going back to an inefficient system of two tax regimes.

There just aren't any easy answers.

Cheers

Greg

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No, no easy answers and history shows that things are going to go where they're going to go in spite of best intentions. Globalization is a very old notion, the largest and most successful example being the period between 1896 and 1914 when the world's economic powers were all on the gold standard, a highly-controversial and increasingly unpopular notion at the time. Yet these notions aren't discussed today, as though what we have chosen to live in is all new. Such notions do not lend themselves easily to the modern categories of "left" and "right", and in fact conservatism and liberalism have completely switched places over the past thirty years.

The point of all this meandering, which is necessarily far too brief to provide an accurate picture of economic forces is to highlight the effects of a political economy on risk-intensive industries such as nuclear power, medicine/health care and the one I focus upon here, aviation. They can't be done "cheaply"...they can be done perhaps "inexpensively" but that notion incorporates the idea of awareness of the risks of cutting too close to the bone, as aviation has been forced to do, in my view.

Don

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