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AF 447 Thread No. 12

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AF 447 Thread No. 12

Old 14th Aug 2014, 15:17
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Originally Posted by Cool Guys
You have changed the subject. I have not studied the A320 development enough to be able to spout off datum's about it.
I haven't changed the subject, I was simply responding to this :
Originally Posted by Cool Guys
In industries that produce equipment that can kill people if it goes wrong, those who are careful about adopting new non validated technologies pose far fewer risks than those who accept new technologies without proper evaluation.
with the assertion that the fourth-gen Airbus flight deck layout and FBW systems were very carefully evaluated before adoption.

Who is disputing its fine safety record?
Roulis, it would appear.

The subject of our original thread drift was about posters’ comments that you nullified using your dubious statistical evidence based on a very small sample base.
Not at all - I wasn't trying to prove anything conclusively via stats, merely backing up my own assertion with multiple anecdotal incidences where connected "conventional" controls did not make a difference, in spite of what those who prefer that layout would claim.

The only conclusion one can draw from your comments is you think these posters are reactionaries. We have differing views.
I think there's a reactionary tendency with some of those posters, yes - but I was speaking more generally. When the A320 was introduced, there was a distinct group of the piloting fraternity who made various claims about how the passive sidesticks and FBW technology were designed specifically to "take pilots out of the loop", and would eventually cause serious safety issues by that same design. Not only was the first assertion untrue, but also neither has come to pass. That's all I'm saying.

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Old 14th Aug 2014, 22:05
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Not only was the first assertion untrue, but also neither has come to pass. That's all I'm saying.
Methink that removing pilot etc .. will not come because FBW or any automation ... but instead as a logical continuation of statistics studies
Indeed the old statistics indicate that percentage of accidents occurred by structural defects ... then it came the time of mechanical problems (engines and others) and now the statistics show an increasing number of accidents due to "pilot error"
The statistics show that it should therefore (for the better) replace the pilot with something else to solve this problem like it was performed for structures and engines
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Old 14th Aug 2014, 23:19
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Statistics Studied

Your suggestion might be a very logical progression of thought if ONLY the “old statistics” that showed the defects that occurred in engines, structures, or instruments where corrected by doing away with engines, structures, and instruments. However, airplanes of today have not replaced engines, structures, and instruments with “something else!” We still HAVE engines, structures, and instruments – but the ones that we have now have been evaluated and substantially improved. So … the logic that you have recommended really is the following: We need to evaluate how we train today’s pilots and then substantially improve that training, and thereby, improve the competency of those pilots. Only when we can replace engines with something else, replace structures with something else, and replace instruments with something else, will we even approach a time when we might consider replacing pilots with something else.
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Old 15th Aug 2014, 05:00
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I think there's a reactionary tendency with some of those posters, yes....
Hi Dozy, I understand where you are coming from.
There are some seemly very experienced pilots here who post their opinions based on many hours flying with their bums in the pilot’s seat. You think they are just being reactionary and your not so humble opinion is based on anecdotal incidences”
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Old 15th Aug 2014, 08:03
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Originally Posted by roulishollandais
Originally Posted by DozyWanabee
safety record
We could hope much better records than AF447 and such wonderful flights.
Originally Posted by DozyWanabee
: Who is disputing its fine safety record?
Roulis, it would appear.
Originally Posted by AirRabbitt
We need to evaluate how we train today’s pilots and then substantially improve that training, and thereby, improve the competency of those pilots.
All the problems of automation and systems, decreasing safety statistics by scandalous accidents where pilots lost their airworthyness (AF447, Habsheim, Asiana, aso) in FBW are the result of the choice of regulators, airlines, and manufacturors to hire, select, train ignorant pilots -not fighting fake licenses , forgetting the role of the third man in the cockpit, using less corporate test pilots and test engineers independant from private industry i.e.) aswell in flight (no more aerobatics i.e.), in maths (not increased to dynamic systems used by FBW), and in engineering (former pilots made human teams with mecaniks and aircraft conceptors). That science was open, but today copying and counterfacts of systems have build a world of secrecy and paranoia which destroys spread of knowledge to pilots' community.
That is why I like PPRuNe! who allows us to share better) but it is not enough to stop that nightmare of new generation accidents who are so sad, and decrease systems' credibility and statistics which should be better. Remind I'm both a pilot and IT guy, pluridisciplinarity is the limit I trust.
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Old 15th Aug 2014, 21:51
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Originally Posted by Cool Guys
There are some seemly very experienced pilots here who post their opinions based on many hours flying with their bums in the pilot’s seat. You think they are just being reactionary and your not so humble opinion is based on “anecdotal incidences”
Not at all. To suggest an extreme hypothetical example, if you took a group of people who had years of experience driving a Ford Model T (which had a completely different pedal and gear layout to today's de facto standard) and put them in a modern car, they would have difficulty operating it and would no doubt tell you that the modern car is inferior and less intuitive to operate than the Model T they are used to driving. And from their point of view that position would be absolutely true.

To bring that example closer to the subject at hand, another "crux" point in aviation, particularly in the US, was around the introduction of the Boeing 727 - which made jet operations out of smaller fields (and therefore previously the preserve of propliners) possible for the first time. There were quite a few nasty crashes early in the life of the B727 caused by crews bleeding off too much speed on the approach and not taking into account the extra time required for a jet engine to spool up and provide thrust compared to a prop-driven airliner. This did not mean that propliners were inherently safer - in fact within a decade or so it would become apparent that the introduction of the jet engine was one of the single most significant improvements to safety there had been in civil aviation, but it took time for the necessary changes in approach and attitude to "bed in".

Regarding Airbus, there's a whole political dimension to the subject which is mind-numbingly boring, but the overriding fact is that - just as before - after an initial period of getting used to the technology, the setup has been proven to work well, and as safely as any other setup currently flying.

Originally Posted by roulishollandais
All the problems of automation and systems, decreasing safety statistics by scandalous accidents where pilots lost their airworthyness (AF447, Habsheim, Asiana, aso)
Oh, please - NWA 6231 was more-or-less circumstantially identical to AF447, and pre-dated the introduction of civil FBW by 14 years. Habsheim was flown manually, and the Asiana accident had a whole slew of additional contributory factors.

in FBW are the result of the choice of regulators, airlines, and manufacturors to hire, select, train ignorant pilots
Rubbish. FBW refers to an electronic connection between the flight controls and flight surfaces - nothing more.

using less corporate test pilots and test engineers independant from private industry i.e.)
As I said before, Gordon Corps (chief pilot engineer on the A320 project and chief safety engineer) had been a certification pilot for the UK ARB (one of the most respected testing and certification bodies in the world) for around two decades prior to being hired by Airbus - it was that experience that they wanted. And they wanted him to make the product safe, not toe any company line.

and in engineering (former pilots made human teams with mecaniks and aircraft conceptors).
Which was exactly what Airbus did with their FBW line, and I'm sure Boeing did too.

That science was open, but today copying and counterfacts of systems have build a world of secrecy and paranoia which destroys spread of knowledge to pilots' community.
Again, rubbish. The block diagrams in Airbus FCOMs are at the same level of detail as those available to pilots and FEs of prior designs, if not more so.
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Old 15th Aug 2014, 22:52
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Divers DozyWanabee
Originally Posted by roulishollandais
All the problems of automation and systems {...}in FBW are the result of the choice of regulators, airlines, and manufacturors to hire, select, train ignorant pilots
"problems" is the subject of that sentence, not "FBW" !!!

Pilots are so ignorant of systems that they are unable to draw or understand a block diagram ; remember the discussions about feedback, THS or SS !!!

I fear BZ used only Gordon Corps's name as alibi for insiders. The book of BZ shows the point of view of BZ. Franz Joseph Strauss was much more important in BZ's mind... behind himself and Baud.

Unions felt -with some realism- to be let outside the human teams. That means the most of the pilots were considered as strangers.

NWA6231 is typically a misjudgement, very different from the FOG in the brains of the crew of AF447, Habsheim or Asiana.

Last edited by roulishollandais; 15th Aug 2014 at 22:54. Reason: adress
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Old 15th Aug 2014, 23:33
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Hello roulis;

We used to have the DC8's systems memorized. We had to be able to draw the terminal and airport charts of Chicago and New York as part of the route check-out on these terminals. We also had to know Morse Code at 5wpm and draw models of frontal weather from the forecasts and SA's, (now METARS), prior to graduating from our initial airline groundschool of two months.

Gradually, as more complex aircraft entered service, the "Need-to-Know" concept took "knowing"'s place. It wasn't possible to know all there was to know about the airplane one flew. So training priorites had to be adjusted and everyone was making it up as they went, particularly when the Airbus was introduced. Even reading the books didn't fulfill the need to know however, because they were very thin on information. So, (personally) I went to the AMMs to learn, (as I'm sure others did).

Most of the time it worked well. When things are going well, flying is easy, but that's not the reason we're there, (and it's the reason why there will never be a pilotless commercial air transport system that replaces the scale of aviation services we have today).

Today, much of this knowledge is handled by software. Also, we now have an entire generation of pilots in the cockpit who grew up interacting with computers and know them intuitively.

The difficulty arises when the assumptions are made that computers "are" airplanes and "know" aerodynamics, etc, etc.

I think you are expressing some important notions regarding competency, knowledge, capacity and their polar opposites. The mistakes are made by both management and the pilot group, the first in assuming that because the airplanes they purchase have sophisticated software autoflight systems which reduce the need for training and competence, and the second group in assuming a relaxed and cold-soup-accepting stance when it comes to automation and both the requirements and the inviolable rules of aviation regarding personal knowledge, ability, skill and competency. That is the essence that makes a pilot a "professional" vice merely a journeyman in the cockpit.

It is up to both groups to get their act together. By and large, from what I see at conferences and in those associations I continue to maintain with aviation after retirement, that is happening. But we are indeed in a major transition phase between analog and digital flight even as the fatal accident rate remains remarkably, enviously low.
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Old 16th Aug 2014, 00:40
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Hi Dozy,

Originally posted by Dozy: Oh, please - NWA 6231 was more-or-less circumstantially identical to AF447, and pre-dated the introduction of civil FBW by 14 years.
Would you explain exactly why, in your opinion, NWA 6231 is circumstantially identical to AF447 other than the fact they both stalled and crashed? Exactly what caused the demise of NWA 6231?

Last edited by Turbine D; 16th Aug 2014 at 00:42. Reason: Simplification
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Old 16th Aug 2014, 01:53
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Originally Posted by Turbine D
Exactly what caused the demise of NWA 6231?
Summary from WikiP:

Investigators found that the pitot heads had ice damage which caused the crew to receive incorrect airspeed readings. The crew, believing the readings were true, pulled back on the control column and raised the nose, which caused the aircraft to stall.
I figure that's fairly close to AF447 (and Birgenair 301 for that matter)...

Originally Posted by roulishollandais
Pilots are so ignorant of systems that they are unable to draw or understand a block diagram ;
On what are you basing this assertion?

remember the discussions about feedback, THS or SS !!!
Which discussions? There have been more than a few!

I fear BZ used only Gordon Corps's name as alibi for insiders.
You fear incorrectly. A cursory search of Flight International's archives will tell you that GC was very much the lead pilot engineer.

The book of BZ shows the point of view of BZ.
Which one - "Airbus Cow Boys"?

Franz Joseph Strauss was much more important in BZ's mind... behind himself and Baud.
Doesn't matter what BZ thought - GC was the lead engineering test pilot for the A320 project for the very reason that he understood safety and certification needs inside-out. I have it on very good authority that while BZ was engineering lead in name, he had very little to do with the day-to-day work.

Unions felt -with some realism- to be let outside the human teams.
No, the SNPL had a long-standing grievance with Airbus over the deletion of the FE station from the original A300 back in 1972, and as such sought to thwart Airbus at every turn ever since.

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Old 16th Aug 2014, 10:37
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after an initial period of getting used to the technology, the setup has been proven to work well, and as safely as any other setup currently flying.
I don't doubt that.
There were many new technologies implemented in the 320. Obviously most of these new technologies were improvements and overall the end result was a fine machine. However that does not mean all those new technologies were improvements. There is a chance some were in fact a step backwards, even if by a small amount. How can you pick out some anecdotal incidences about the 320 in general and conclude that one of those many new technologies (side sticks with no tactile feed back) is in fact an improvement? Particularly when there are a bunch of experienced pilots voicing their concerns?
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Old 16th Aug 2014, 12:37
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Original Quote by Dozy Summary from WikiP:

Quote:
Investigators found that the pitot heads had ice damage which caused the crew to receive incorrect airspeed readings. The crew, believing the readings were true, pulled back on the control column and raised the nose, which caused the aircraft to stall.
I figure that's fairly close to AF447
You figured wrong. The NWA crash was caused by the crew forgetting to turn on the pitot heaters before departing KJFK on a cold rainy winter late afternoon. As they climbed out, the pitots froze creating a false high speed instrument reading in the cockpit. They responded to this erroneous reading by increasing the climb angle to the point the aircraft stalled. So how is that fairly close to AF447 that had no speed readings except brief intermittent ones on the way down after stalling from cruise altitude?
I think you are taking poetic liberties to support your assertions that don't fit well in the Tech Log, maybe in Rumors and News…

http://www.airdisaster.com/reports/ntsb/AAR75-13.pdf

Last edited by Turbine D; 16th Aug 2014 at 12:52. Reason: Content correction and addition
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Old 16th Aug 2014, 18:14
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@Turbine D - I did say "fairly close", by which I meant basic aspects only - namely frozen pitot tubes -> crew (mistakenly) pulls up -> aircraft stalls and crashes. Obviously not every aspect is the same.
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Old 18th Aug 2014, 11:51
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Hello PJ2,

Apologize for my late answer to you post #307. You were doing an acurate description of evolution of pilots' knowledge, functions and actual work.

-Intuitive knowledge of new generation helps to learn but not to overcome every aerodynamic situation like degenerating dutch rolls (I'm seeing that USAF decided to fight them forever if possible) or actual stalls in limited airliners and intuitive knowledge does not protect against the drift of airworthyness due to abusive complexity to manage in some mishap cockpits.

The younger generation of pilots and engineers and managers grew up with software : but we know (at least some of us in IT know) that software grew bad, accepting many bugs appearing in subit countrywide pans of electricity, trains, files with mistakes and losses, subprimes, and money scandals (list is unlimited).
I want to point strongly the fact that software's quality is mostly bad and generally accepts an uncomputed rate of reliability and what it means in real life for victims of accidents.

- The description of the both point of view of management teams and pilots (and pilots'unions) points an ordinary human behaviour : to be safer we set two (or more) levels of responsibility to double the verifications, but quickly, to avoid competition for exemple, every "responsible" man/organisation watches only the half of the chain... and a little later the verifications are no more doubled but divided by two, and if an accident happens you will no more find any "reponsible" person.

Exemple 1 about that responsibility dilution :
After the Ariane 501 crash and his wonderful J.L.Lions report, the engineer Ducrocq commented :"Everyone was responsible, so nobody is responsible" ; final cost was 8 billions French Franks ; in the 12 pages report I noted 99 mistakes had been done, from around 80 types of failures, not far of all the failures you can do in software...

Exemple 2 : In the 1992 Air Inter Ste Odile crash I discovered that the height of the mountain the Bloss on the official Instrument approach chart was false. The 2710 FT summit (IGN) of the Bloss against which the wreckage was found at 2620 FT (BEA report) was inside a highest level line of 2500 FT. It appeared to me that the mistakes was years old, and around 7-8 organisations had shared the responsibility of drawing, publishing, using that chart during these years. More, in the same highest line level of 2500 FT was the very popular well known statue of Ste Odile seen by any and many ATCs every day for departure or arrival (depending of the wind) inside of the arrival or departure cone, but no ATC asked himself how that statue could figure inside the 2500 FT line of their IAC which was the always present before their eyes on their table, main tool. (764m Mont Sainte-Odile ? Wikipédia ).
Happily that official VORTAC approach procedure respected the margins.
The BEA did not strickly lie about that -so that the most of you discover these facts now!- but wrote few very difficult understandable sentences if any about theses differences and read the report without noting the faulty height.

Not only that, Air France drawed their own charts (with ATLAS). Surely they used the wrong chart, rectified the height, but deleted the ICAO level lines, and deleted the mention "FAF" as they did on all their approach charts (1992) before that accident. Again more than 10 organisations drawed, published and used the chart without the "FAF" position ; that loss allowed the plane to descend at 1340 FT after 9 NM to STR VOR instead waiting at 3660 FT until 7NM to STR. Experts said nothing, BEA no-commented turning around again too. Two derogations had been given (BEA report) to draw and use a CDA and everyone forgot it was a VOR-DME (or VORTAC) approach. The expert Belotti said me he ignored the PROMIN ICAO and French law's rule of 15% obstacle clearance and had honesty to no more came to the trial...
Since that trial the list of persons who signed the crash reports (around 15 in that crash) is no more public...

We need to have multiple levels of verifications and cross-checks for some critical points, it is important to don't transform them in crash swisscheeze.

PJ2 we are used to read how seriously you are studying hard the folders where you were and still are involved, and in connection with others in the safety chain, which happily is more than 99.9 or 99.99 ;-) or "enviously low". I wanted to say that, despite working together as you are doing, management and pilots are not in a common balance. The latter pay with their lifes the mistakes -as do the passengers-.

And my obligation, being aware of the high unvisible criticity of flying softwares (which may be analogic too) is to move the eventual danger flag existing in that world, decreasing -in my conviction- the safety level under its possibility.

Going in that new world doesn't allow to leave historical airworthyness in abusive complexity that brain is not sure to masterize in the short minutes, or seconds or less allowed for decision in flight.

Thanks for your always appreciated very professional posts.

Last edited by roulishollandais; 18th Aug 2014 at 17:21. Reason: altitudes bloss and ste-odile, swisscheese, spelling, highest
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Old 18th Aug 2014, 19:46
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@Winnerhofer:

From the paper you just linked -

“Go ahead, you have the controls. We are still in TOGO eh.” TOGO, short for ‘touch and go’ refers to a process of regaining lift at low altitude, something that occurs when a pilot suddenly abandons a landing and reinitiates ascent of the aircraft at the last possible moment.
Ouch. More research required.
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Old 18th Aug 2014, 21:48
  #276 (permalink)  
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roulis;

I wanted to say that, despite working together as you are doing, management and pilots are not in a common balance. The latter pay with their lifes the mistakes -as do the passengers-.
As I have just finished watching ITVs examination of British aviation and thence the story of Shipwrecks which I found fascinating in the quality and quantity of the parallels with the aviation industry (in terms of private power, invisible accountability and unbridled profit at the expense of thousands), I have to say that aviation has taken/learned a great deal from 19th Century shipping.

It has to be acknowledged that if aviation doesn't make money for it's owners/investors/employees then it will fail no matter how accountable, moral or socially-responsible it is. That's a principle of human endeavour - dreams, imagination and invention may be the seeds and even the energy for such enterprises but it has to survive on it's own. This realization changed the shipping industry, (just read the history of Plimsoll and recall how he was treated by the British Parliament), and I think for many obvious reasons, aviation learned faster.

Today, Safety is no longer a backwater appointment or even a career-ending management position as it was even two or three decades ago, within an airline's bureacracy, and programs that were seen as interfering with profitability and share price are today widely accepted as necessary partners in the enterprise.

Having been involved in management - pilot (union) work for many years, I have seen the positive changes at least in two companies, particularly where data analysis and the larger principles of SMS are "in play". While there is very much a need for the regulator's presence and oversight, SMS is now a far better way to do aviation's business.

One aspect of this question you might examine is the question of what changes a culture. In Canada we had a such a turning point with the takeoff accident at Dryden. The result was a public inquiry into aviation in Canada, led by Mr. Justice Virgil Moshansky called the Commission of Inquiry into the Air Ontario Crash at Dryden, Ontario (Canada), popularly known as the Dryden Inquiry. It is well worth reading, particularly Vol's II & III. The Dryden Inquiry was a game-changer in Canada; the reverberations from Moshansky's work haven't stopped yet.

I'm not going to dwell on the details here, but the question of change itself is an important one for other country's regulators to examine, if only to reify their own approaches to this partnership of financial success and flight safety, in which pilots and their representatives are full partners and play an important role, even as some who would quietly seek otherwise dismiss pilots' views as "unionism" and "playing the safety card".

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Old 19th Aug 2014, 09:19
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Discovering Samuel Plimsoll! Perhaps he is not so far in today's aviation !!!
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Old 19th Aug 2014, 09:59
  #278 (permalink)  
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I think he has everything to do with aviation, but of course he woudn't have known it! It shows that the human and corporate behaviours and the principles that govern success and failure are the same.

One of the most significant insights developed in aviation safety came from Charles Perrow, when he wrote "Normal Accidents" in 1984. The process of changing our notions about "pilot error" and our notions of cause and blame began with Perrow and today are an integral part of SMS.

The other very significant change that arose out of the Dryden Inquiry, (as well as out of other industries such as coal mining - ...yes, there is a connection!), and which became a crucial part of SMS from the start, was the notion of the "Accountable Executive". In Canada it was called the "Westray Law" after a mining accident killed 26 miners and the courts held the executives accountable because they knew of the dangers and ignored them.

The notion of normal accidents is in contrast to the notion of "pilot error". The understanding that accidents occurred when people thought they were doing exactly the right thing opened the door to new understandings of why accidents occur. The concept of "organizational accidents" arose out of Perrow's work.

Although preceded by Bill Starbuck's paper, "Challenger: Fine-tuning the Odds Until Something Breaks", the finest explication of these notions is, in my view, Diane Vaughan's seminal sociological work, "
The Challenger Launch Decision The Challenger Launch Decision
".

There is a tremendous history behind the spectacular drop in fatal accidents and hull losses seen in the Airbus paper posted by A33Zab, (it should be noted that Boeing has been doing this same kind of study for a long time; the latest issue can be found here), began to change with the emergence of these important, broader notions about why machines and people fail. It is only the lawyers who seem to continue to focus on those who arrived at the accident site first...the pilots.

It is getting easier to make the business case so that shareholders, management and lawyers alike see that spending money on "nothing happening", (i.e., no accidents), is a good thing. These enlightened approaches, still resisted by corporate interests and their lawyers, are gradually showing that there is profit in operating safely, mainly because these days accidents do indeed cost far more than their prevention.
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Old 19th Aug 2014, 10:37
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I don"t think that "safety increases profit" ! Accidents increase PIB, GDP much more. The benefit of safety is only marginal and false money of bankers jumps in the safety closed loop.

SMS is surely a great improvement, but must be seen as a procedure not a social procedure, but a brain understanding unless the lawyers jump in the loop with worlds and worlds !

I still don't see the tremendous improvement of safety in Airbus statistics posted by A33Zab as due to FBW, but the pages 9 and 10 showing the excessive long time 10 years to stabilize the FBW accidents (not enough testing of flying software) and the decreasing level of pilot (accidents' rate x3 from 1994 to 2013) in not limited A/C.

I don't want to consider safety issue in aviation as culture problem. It is not the ICAO concept after a World War. Accidents result of actual facts. "Culture" the best way to mix culpability to gestures,isn't?

Nearly everybody is convicted inside of himself that he is doing the right thing...

Last edited by roulishollandais; 19th Aug 2014 at 16:57. Reason: spelling, ICAO, testing flying software, "is"
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Old 20th Aug 2014, 00:03
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Originally Posted by roulishollandais
but the pages 9 and 10 showing the excessive long time 10 years to stabilize the FBW accidents (not enough testing of flying software) and the decreasing level of pilot (accidents' rate x3 from 1994 to 2013) in not limited A/C.
As I said before, you're reading that wrong. For one thing there have been zero accidents in which the FBW software was a major factor since the A320's introduction over 25 years ago. Every new generation of jet has had a greater number of accidents and incidents in the early years of operation.

I'll say it again - the dotted line in the graphs indicates that less than a million flights of that type were made, so the ratio will appear higher if the number of accidents is divided by that lesser number. This is why the line is dotted, because the statistical baseline for the graph has not yet been met.

This also applies to the dotted line referring to second-gen jets - the ratio is skewed by the minimum required number of flights (a million) not being reached - not because piloting abilities without assistance have been reduced as you seem to think.

Again - the other main reason the second-gen chart climbs slightly before dropping below a million flights is because older aircraft start to have more technical issues as they age, and this is compounded by those older aircraft being sold on from major airlines to smaller operators, and to developing countries, where the safety infrastructure is not as rigorous.

[EDIT: @roulis - I've already explained how the points you make about software aren't really valid when talking about the Airbus FBW system. I'm not going to repeat meself, but here's a link to the first post : http://www.pprune.org/tech-log/52803...ml#post8237990 ]

Last edited by DozyWannabe; 20th Aug 2014 at 23:19.
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