How safe is (airbus) fly by wire? Airbus A330/340 and A320 family emergency AD
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As for the SNPL, their opinion has to be seen in the light of their consistent opposition to Airbus technology since the introduction of the first two-pilot glass cockpit on the A310 in 1983, and the Habsheim affair in 1988. As usual, some of their demands are rhetorical; others may be arguable.
The opinion of a professional pilots union, even french, are to be taken extemely seriously in terms of safety, any other approach is biased and puts the author into a somewhat shaded light.
It is time to accept that too many parties ask for a closer look into the Airbus design. The bipartisan comitee from the 90's (i can't remember the title), an article of your homonym the much regarded Robert Scott, a comparative article in the Swiss aviation publication Cockpit and even Sullys contribution, that's too many professionals who ask for the very same corrections, notwithstanding the many contributors on pprune.
I am tired of all the smokes amd mirrors that are set up to take the attention away from these critics. I am just as tired of being cried down by people who have not operated the system themselves, or those who have operated only this very system. Some of us have been priviledged to fly the other major competitors as well and no longer silently accept to be disregarded.
Where there's smoke, there's a fire and in aviation we tend to take fire seriously, even if it's only a warning, don't we? I hope we at least agree on that.
Last edited by Gretchenfrage; 30th Dec 2012 at 05:17.
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I love the smell of false equivalency in the morning...
Says who? There's no belittling going on here, simply a reasonable request that the vocal minority acknowledge that they are just that - unless they can prove otherwise - and that they answer questions put to them honestly.
Given that this particular union's motives are reasonably considered somewhat suspect in terms of objectivity, Chris's scepticism is not only reasonable, but also logical. Given the 29 years (5 of which pre-date the introduction of Airbus FBW) of opposition from factions within this union, it's a little rich to accuse others of bias in this matter.
This is a thoroughly false assertion. The naysayers are, and always have been, a minority - no matter how vocal they have been. If the "bipartisan committee" you refer to is the IFALPA ADO group, then the non-binding resolution dates from the '80s - not the '90s - and is due for a re-appraisal soon (according to current member Capt. Terry Lutz). Capt. Sullenberger's view on the matter amounted to little more than a commentary - he certainly did not call for a change in the systems design.
There are at most maybe 10 contributors on PPRuNe who hold a view on the matter comparable to yours (and who make it their business to zero in on every Airbus thread to make their viewpoint known). They may be consistently vocal, but that does not indicate a consensus on the matter - not even slightly.
What smoke and mirrors? The "Airbus-sceptic" position has been repeatedly challenged with cogent arguments from parties that include as many pilots as non-pilots. Some parties among the sceptics have repeatedly promised new evidence and yet failed to deliver. Neither you nor anyone else among the sceptics has been able to prove your position is held by a majority of pilots, let alone whether that position is objectively correct.
And yet I can recall clearly posts by pilots on here who have openly admitted to missing the relative simplicity and reliability of the Airbus system, having transferred to other types. I repeat - no-one, least of all myself, is trying to disrespect you for the position you hold. On the other hand, if you try to portray your position as reflective of a majority of pilots without supporting evidence, then don't be surprised if you and your fellow sceptics are challenged on that point.
Thus far there is no smoke (in the form of objective data) suggesting Airbus FBW is any less safe than the alternatives available. None. Neither you nor anyone else is capable of wishing such data into being, no matter how much you may want it to be so.
The opinion of a professional pilots union, even french, are to be taken extemely seriously in terms of safety, any other approach is biased and puts the author into a somewhat shaded light.
It is time to accept that too many parties ask for a closer look into the Airbus design. The bipartisan comitee from the 90's (i can't remember the title), an article of your homonym the much regarded Robert Scott, a comparative article in the Swiss aviation publication Cockpit and even Sullys contribution, that's too many professionals who ask for the very same corrections
notwithstanding the many contributors on pprune.
I am tired of all the smokes amd mirrors that are set up to take the attention away from these critics.
I am just as tired of being cried down by people who have not operated the system themselves, or those who have operated only this very system. Some of us have been priviledged to fly the other major competitors as well and no longer silently accept to be disregarded.
Where there's smoke, there's a fire and in aviation we tend to take fire seriously, even if it's only a warning, don't we? I hope we at least agree on that.
Last edited by DozyWannabe; 30th Dec 2012 at 06:11.
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Thus far there is no smoke (in the form of objective data) suggesting Airbus FBW is any less safe than the alternatives available. None. Neither you nor anyone else is capable of wishing such data into being, no matter how much you may want it to be so.
For airbus there are at least 4 where it is questionable if the protections did not make matters worse.
As for your heroic statement that the EVA pilots correctly switched off ADR's... Since AF447 every airbus pilot will know how to get the aircraft in direct law!
Last edited by 737Jock; 30th Dec 2012 at 06:29.
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There's no belittling going on here, simply a reasonable request that the vocal minority acknowledge that they are just that.
The naysayers are, and always have been, a minority - no matter how vocal they have been.
The naysayers are, and always have been, a minority - no matter how vocal they have been.
And what other than belitteling is just that? How educated is it to call a minority to acknowledge what they are and by this implying that their opinion is worth less than the majority’s? Isn’t it the very right, legitimate and civilised weapon for a minority to speak up?
Are we back to those kind of times??
If the "bipartisan committeee" you refer to is the IFALPA ADO group, then the non-binding resolution dates from the '80s - not the '90s - and is due for a re-appraisal soon (according to current member Capt. Terry Lutz)
Such self imposed “immunity” is revealing and exactly what many criticise.
Thus far there is no smoke (in the form of objective data) suggesting Airbus FBW is any less safe than the alternatives available. None. Neither you nor anyone else is capable of wishing such data into being, no matter how much you may want it to be so.
Additionally there are the beloved statistics (hull losses and fatalities) that point clearly to one side. You can always debate about the higher number of airframes of one, but you cannot dismiss that one system has had NO fatalities so far and the other one has. That in itself should raise big flags if your concern is safety at all!
I stand by my argument, even if I am a despised minority:
The Airbus system needs modification.
Happy new year, I'm leaving for the party now.
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There are no accidents or incidents for any of the above types that can be attributed to the FBW systems, at least in isolation. Automation is a different matter, but automation and FBW are two very distinct aspects of airliner operation. For example, there are plenty of automation-related hull losses for the B757 and B767, neither of which are FBW. The Turkish 737 that pancaked short of Schiphol can also be considered an automation-related accident but - as you know - the 738 is certainly not an FBW design. In that case, moving thrust levers signalled a reduction in thrust way beyond what the crew were expecting, but they never picked up on it. The same goes for the Birgenair B757 crash where despite having the yoke in front of him, the F/O neither stopped the Captain from pulling into a stall nor corrected him after he had done so.
The truth is that while it may be comforting to believe that a more traditional setup will make fault diagnosis easier for pilots, the evidence does not support that supposition. The PF of AF447 may have pulled into a stall, but so did the Captain of Birgenair 301 and ColganAir - neither of which had spent any time on a FBW Airbus.
Similarly while I do not doubt the existence of design problems in the Airbus systems, I am equally convinced that some remain in the B737s that you fly among others.
Maybe, but ….. is only criticism of the Airbus system due for a re-appraisal? You do imply by this that the system would be immune to a re-appraisal itself, don’t you?
The smoke is admittedly not in form of objective data, but that is the very nature of “smoke” used as a metaphor in this case by the way. It is the many threads on forums, in the press and the many publications about the matter that form the smoke. There is not a tiny fraction of the same for the competing system, which tells a story!
Additionally there are the beloved statistics (hull losses and fatalities) that point clearly to one side. You can always debate about the higher number of airframes of one, but you cannot dismiss that one system has had NO fatalities so far and the other one has. That in itself should raise big flags if your concern is safety at all!
I stand by my argument, even if I am a despised minority
Last edited by DozyWannabe; 30th Dec 2012 at 07:04.
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Originally Posted by Chris Scott
your own knowledge of the Airbus cockpit remains unashamedly negligible.
Having 'grown up' in aviation as a real pilot (unlike many on here) well before the magenta line days I merely try to look at it from a real pilot's pov (unlike many on here) and comment on what I would wish to see/have (and find myself amazed at some of what I do see).
By the way, if you care to look at a dictionary, you will see that 'bigotry' can be a subjective word.
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The AB FBW controls with all their complex protections and laws obviously work OK in normal situations and statisically there seems to be no fundamental issues with the system however there seems to be some agreement from those who fly the plane that there are some refinements that could be made. No device made from a complex system of interacting mechanical and electrical components is perfect. There is always room for improvements. With any breakdown, failure or crash there is an opportunity for improvement and refinement. The requests from the AF pilots union seem like a good list of sensible refinements. The AB engineers may have all ready been looking into these points. At the end of the day we must learn and improve the product so there is less opportunity for further accidents. I hope AB don’t try to save face and insist their existing system is perfect. I hope they can be professional, look at it objectively and refine their product to make a better,safer plane.
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Well that's a load of BS Dozy... Nobody was talking hull losses.
But while we are at it only one 777 has been a hull loss and FBW could not have saved that nor did it play a role.
Airbus however has had many unfortunate incidents, due either the system not being understood or simply the FBW fighting with the pilots for control. Some crashed!
But while we are at it only one 777 has been a hull loss and FBW could not have saved that nor did it play a role.
Airbus however has had many unfortunate incidents, due either the system not being understood or simply the FBW fighting with the pilots for control. Some crashed!
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Originally Posted by CONF iture
Question for HazelNuts39, at which angle the AoA probes should freeze for Alpha Floor to activate before M.53 is reached ?
Originally Posted by CONF iture
I believe the value for alpha-floor can be variable somewhere between alpha-prot and alpha-max.
Last edited by HazelNuts39; 30th Dec 2012 at 20:36.
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I'll ask again, jcjeant:
- Quote:
Originally Posted by the Google translation
Airbus could not regain control of their aircraft when they reproduced stall Rio .
- do we have any information on this 'test'? Have I missed it on the forum?
Originally Posted by the Google translation
Airbus could not regain control of their aircraft when they reproduced stall Rio .
- do we have any information on this 'test'? Have I missed it on the forum?
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Don't get automation confused with FBW - two very different things. In fact the automation on the A320 is no more complex than that on your 737NG, which is why automation-related crashes and incidents are comparable in number across all types and manufacturers.
@Cool Guys - read Chris Scott's post. The SNPL press release is a political statement, and their "requested changes" are not common-sense. They constitute a fundamental misunderstanding of the design and if implemented would not only have very little - at best - in the way of safety benefit, but would also effectively undermine the commercial edge Airbus have, which is arguably the SNPL's goal.
Last edited by DozyWannabe; 30th Dec 2012 at 17:13.
Some of these exchanges are reminiscent of a Rumour & News thread. Perhaps we might all calm down a bit?
I'll start by admitting that my knowledge of Boeing-style FBW is negligible, and flight experience nil; rather like BOAC's in relation to Airbus FBW. ** That's why I never presume to comment favourably or otherwise on a Boeing FBW package that seems to have many merits - as does the Airbus one. As I said, it's a pity that BOAC's condemnations are based - as in the case of Lyman/Bearfoil - mainly on intuition and hearsay.
Lyman,
Further to your comments on Gordon Corps, have you not heard of the US Army Corps? The American pronunciation may be different from ours, where the p and s are normally silent. However, when my airline took delivery of the A310 in 1984, and Airbus pilots were training us, there was one West African service crewed by Captains Dave Deadman and Gordon Corps.
DozyWannabe
(sorry for the spelling error in my previous),
Thought you'd appreciate "rose-tinted spectacles" in relation to a product of "la Ville Rose"?
You talk of Airbus's departure from existing flight-control-system design causing "consternation... particularly in the piloting community" I think the arguments that we in the technical study groups of BALPA and IFALPA raised in the mid-1980s in opposing the non-driven throttle levers and non-interconnected sidesticks, were correct, but their ergonomic deficiencies have caused fewer problems than we predicted. (Of course the other big concern was the general reliability of computer systems, including Airbus's decision to use modest, tried-and-tested, commercial microchips - rather than purpose-built, mathematically-correct ones - and their decision to avoid triplex architecture. It was also widely predicted that system anomalies would be untraceable by accident investigators. Nevertheless, we didn't black-ball the inevitable.)
The day after tomorrow (January 1st) will be the 25th anniversary of the start at Blagnac of the first BCAL/BA A320 pilot-conversion course (AF's first course had started a few days earlier). Except for two of us line pilots, plus a CAA inspector, the captains were BCAL management, including the A320 project manager. We had come from a variety of aircraft types: the B747-200, DC10-30, and BAC 1-11. Two of us had earlier flown the A310: from 1984-6. Once on the simulator, we quickly adapted to the sidestick, and soon learned to live with the non-driven throttle levers (which, however, provide the sweetest manual-thrust control of any aeroplane I've flown). We had to wait for the completion of mods to the electrical system, and the type to be certificated, before we could fly an aeroplane.
Gretchenfrage,
Although I see you predate me on PPRuNe, I don't recall your User Name from the many Airbus FBW discussions I've contributed to - forgive me. Judging from your post, you are in a similar position. I have no intention to belittle anyone; only to express my opinion, and challenge weak or false arguments (usually politely) when I recognise them. It's apparent on this thread that the flak is coming, as usual, almost entirely from those who are anti-Airbus (and usually praising Boeing); very little is going in the opposite direction. That's fine when the author is someone who has considerable Airbus flight experience, like Conf_iture.
The ideal, however, would be to hear from pilots who are literate, dispassionate and technically perceptive, who have at least several years' flying experience of both FBW philosophies. You seem a little reticent to reveal your own, but do you perhaps fit those criteria?
It may be that some A320 pilots posting here have found themselves on type against their inclination, as a stepping stone to something else - perhaps a bigger Boeing. The A320 has been so successful that it has become the ubiquitous, boring, short-haul workhorse - like the B737 was in the 1980s and '90s. It's no longer the cutting-edge, exciting challenge that I relished 25 years ago. The A330 has been eclipsed for size and range by the B777, so is somewhat lacking in charisma. The A340 got a suitable engine too late in its development because, in the 1980s, Rolls Royce abandoned plans to supply a more powerful engine than the CFM-56. A380 jobs are still at a premium. Are their criticisms influenced in any way by disenchantment, I wonder?
I regard myself as a Francophile, so it gives me no pleasure to point out that my former opposite numbers in SNPL bring a lot of baggage to any discussion on Airbus FBW. By the 1980s, BALPA had a more pragmatic approach to new technology. For instance, we did not demand a third crew member in the A310 cockpit. My copilot on the A320 course was the chairman of the BALPA new-aircraft study group, of which I was a member (as mentioned above). The fact that we were so critical of some of the concepts was extra motivation for doing the conversion; to see for ourselves. Our attitude was sceptical, but positive. If we had discovered anything dangerously unacceptable, we would have been reporting it to the aviation world. We found no such thing, although my friend did manage to persuade Bernard Ziegler to modify the speed index on the ASI during an Airbus/IFALPA meeting the following year. Two fatal accidents later brought AFS ergonomic weaknesses to light. Admittedly, although we were aware of the features concerned, we had failed to predict that they might contribute to an accident, and I don't think SNPL did.
I was an A320 skipper at the time of the Habsheim accident that first summer, the captain of which had overlapped us in Airbus Flight Training. Having looked at the video, formed an understanding of the cause, and listened to the hysteria from the media (and even doom merchants in our own airline), we just had to keep on flying passengers as normal - no thanks to SNPL. When I say that some of SNPL's demands are rhetorical, I mean that we lost the battle for those in the 1980s. I say again, the overall package is good; warts notwithstanding.
737Jock,
There's no doubt that the B777 is an excellent airplane. But, until a few months ago, it was the only Boeing in service with FBW. Also, it is a long-haul type, each A/C performing far fewer flight cycles per year than an A320.
** The last Boeing I flew was the 707. Its only powered flight control was the single rudder, protected by a crude Q-feel unit, and incorporating - on later models - the luxury of a series yaw damper. The ubiquitous FD108 flight director was excellent for its 1970s era. There was a single AP, with a height (altitude) lock. On one occasion, after it failed at top-of-climb out of Caracas, the captain and I took 20-minute turns to hand-fly the big beast home to Gatwick, finishing the cruise at FL410.
I'll start by admitting that my knowledge of Boeing-style FBW is negligible, and flight experience nil; rather like BOAC's in relation to Airbus FBW. ** That's why I never presume to comment favourably or otherwise on a Boeing FBW package that seems to have many merits - as does the Airbus one. As I said, it's a pity that BOAC's condemnations are based - as in the case of Lyman/Bearfoil - mainly on intuition and hearsay.
Lyman,
Further to your comments on Gordon Corps, have you not heard of the US Army Corps? The American pronunciation may be different from ours, where the p and s are normally silent. However, when my airline took delivery of the A310 in 1984, and Airbus pilots were training us, there was one West African service crewed by Captains Dave Deadman and Gordon Corps.
DozyWannabe
(sorry for the spelling error in my previous),
Thought you'd appreciate "rose-tinted spectacles" in relation to a product of "la Ville Rose"?
You talk of Airbus's departure from existing flight-control-system design causing "consternation... particularly in the piloting community" I think the arguments that we in the technical study groups of BALPA and IFALPA raised in the mid-1980s in opposing the non-driven throttle levers and non-interconnected sidesticks, were correct, but their ergonomic deficiencies have caused fewer problems than we predicted. (Of course the other big concern was the general reliability of computer systems, including Airbus's decision to use modest, tried-and-tested, commercial microchips - rather than purpose-built, mathematically-correct ones - and their decision to avoid triplex architecture. It was also widely predicted that system anomalies would be untraceable by accident investigators. Nevertheless, we didn't black-ball the inevitable.)
The day after tomorrow (January 1st) will be the 25th anniversary of the start at Blagnac of the first BCAL/BA A320 pilot-conversion course (AF's first course had started a few days earlier). Except for two of us line pilots, plus a CAA inspector, the captains were BCAL management, including the A320 project manager. We had come from a variety of aircraft types: the B747-200, DC10-30, and BAC 1-11. Two of us had earlier flown the A310: from 1984-6. Once on the simulator, we quickly adapted to the sidestick, and soon learned to live with the non-driven throttle levers (which, however, provide the sweetest manual-thrust control of any aeroplane I've flown). We had to wait for the completion of mods to the electrical system, and the type to be certificated, before we could fly an aeroplane.
Gretchenfrage,
Although I see you predate me on PPRuNe, I don't recall your User Name from the many Airbus FBW discussions I've contributed to - forgive me. Judging from your post, you are in a similar position. I have no intention to belittle anyone; only to express my opinion, and challenge weak or false arguments (usually politely) when I recognise them. It's apparent on this thread that the flak is coming, as usual, almost entirely from those who are anti-Airbus (and usually praising Boeing); very little is going in the opposite direction. That's fine when the author is someone who has considerable Airbus flight experience, like Conf_iture.
The ideal, however, would be to hear from pilots who are literate, dispassionate and technically perceptive, who have at least several years' flying experience of both FBW philosophies. You seem a little reticent to reveal your own, but do you perhaps fit those criteria?
It may be that some A320 pilots posting here have found themselves on type against their inclination, as a stepping stone to something else - perhaps a bigger Boeing. The A320 has been so successful that it has become the ubiquitous, boring, short-haul workhorse - like the B737 was in the 1980s and '90s. It's no longer the cutting-edge, exciting challenge that I relished 25 years ago. The A330 has been eclipsed for size and range by the B777, so is somewhat lacking in charisma. The A340 got a suitable engine too late in its development because, in the 1980s, Rolls Royce abandoned plans to supply a more powerful engine than the CFM-56. A380 jobs are still at a premium. Are their criticisms influenced in any way by disenchantment, I wonder?
I regard myself as a Francophile, so it gives me no pleasure to point out that my former opposite numbers in SNPL bring a lot of baggage to any discussion on Airbus FBW. By the 1980s, BALPA had a more pragmatic approach to new technology. For instance, we did not demand a third crew member in the A310 cockpit. My copilot on the A320 course was the chairman of the BALPA new-aircraft study group, of which I was a member (as mentioned above). The fact that we were so critical of some of the concepts was extra motivation for doing the conversion; to see for ourselves. Our attitude was sceptical, but positive. If we had discovered anything dangerously unacceptable, we would have been reporting it to the aviation world. We found no such thing, although my friend did manage to persuade Bernard Ziegler to modify the speed index on the ASI during an Airbus/IFALPA meeting the following year. Two fatal accidents later brought AFS ergonomic weaknesses to light. Admittedly, although we were aware of the features concerned, we had failed to predict that they might contribute to an accident, and I don't think SNPL did.
I was an A320 skipper at the time of the Habsheim accident that first summer, the captain of which had overlapped us in Airbus Flight Training. Having looked at the video, formed an understanding of the cause, and listened to the hysteria from the media (and even doom merchants in our own airline), we just had to keep on flying passengers as normal - no thanks to SNPL. When I say that some of SNPL's demands are rhetorical, I mean that we lost the battle for those in the 1980s. I say again, the overall package is good; warts notwithstanding.
737Jock,
There's no doubt that the B777 is an excellent airplane. But, until a few months ago, it was the only Boeing in service with FBW. Also, it is a long-haul type, each A/C performing far fewer flight cycles per year than an A320.
** The last Boeing I flew was the 707. Its only powered flight control was the single rudder, protected by a crude Q-feel unit, and incorporating - on later models - the luxury of a series yaw damper. The ubiquitous FD108 flight director was excellent for its 1970s era. There was a single AP, with a height (altitude) lock. On one occasion, after it failed at top-of-climb out of Caracas, the captain and I took 20-minute turns to hand-fly the big beast home to Gatwick, finishing the cruise at FL410.
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Originally Posted by the Google translation
Airbus could not regain control of their aircraft when they reproduced stall Rio ...
Airbus could not regain control of their aircraft when they reproduced stall Rio ...
May I suggest the above translation is from an agenda driven article.
Furthermore, while there are many references within all the AF447 threads in this forum to the inability of current level 3 SIMs to replicate accurately events outside the designed for flight envelope, Airbus may well have incorporated extended data obtained from this fateful flight into a test SIM, and neglected to tell us.
While having a look around, I came across this interesting little report by the NASA Safety Center entitled "What's Happening?" - NASA
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Hi Chris...
In re Corps...
I was trying, badly, it turns out, for some political satire. My President, Obama, presenting an award to a Marine, announced his rank as:
"Corpseman..." no kidding. I forgot DW was UKish, so would not have known.
My bad....
In re Corps...
I was trying, badly, it turns out, for some political satire. My President, Obama, presenting an award to a Marine, announced his rank as:
"Corpseman..." no kidding. I forgot DW was UKish, so would not have known.
My bad....
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Thanks mm - that makes sense..unless......
I'm not sure the NASA paper adds much, but I think the last two ??NASA?? findings are important
•Extensive reliance on automation for normal operations can undermine a time-critical, successful operator recovery from an off-nominal event.If there is a manual mode, operators must become and remain proficient in its use.
•There is no single right answer to the issue of human control versus machine control in human-machine interfaces. But as the need for human intervention follows the value of the system, the need for high-fidelity experience in compound failure scenarios, not just a single component or feature, becomes essential to timely action..
I'm not sure the NASA paper adds much, but I think the last two ??NASA?? findings are important
•Extensive reliance on automation for normal operations can undermine a time-critical, successful operator recovery from an off-nominal event.If there is a manual mode, operators must become and remain proficient in its use.
•There is no single right answer to the issue of human control versus machine control in human-machine interfaces. But as the need for human intervention follows the value of the system, the need for high-fidelity experience in compound failure scenarios, not just a single component or feature, becomes essential to timely action..
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Reminds me of NASA's attitude toward the "shuttle". They reserved the right to take control remotely, but it wasn't until after the Challenger accident that it was pointed out to them that they had forgotten to make provision for remotely lowering the LG!
Something learned, and the necessary mods were made.
Something learned, and the necessary mods were made.
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You talk of Airbus's departure from existing flight-control-system design causing "consternation... particularly in the piloting community" I think the arguments that we in the technical study groups of BALPA and IFALPA raised in the mid-1980s in opposing the non-driven throttle levers and non-interconnected sidesticks, were correct, but their ergonomic deficiencies have caused fewer problems than we predicted.
I'd hope that if you and your colleagues in the technology group had been privy to just how much work went into it at the time, it may have at least eased your worries slightly. The reason the flight controls and thrust levers were designed the way they were had nothing to do with an intent to take anything away from the flight crew, it was simply reasoned that the technology had become reliable enough to make that evolutionary step safe, and provide the feedback in other ways.
I take a little issue with still referring to these factors as "deficiencies" - at this stage, given that their reliability and suitability for the task has been proven I think it can be reduced to "differences".
(Of course the other big concern was the general reliability of computer systems, including Airbus's decision to use modest, tried-and-tested, commercial microchips - rather than purpose-built, mathematically-correct ones - and their decision to avoid triplex architecture. It was also widely predicted that system anomalies would be untraceable by accident investigators. Nevertheless, we didn't black-ball the inevitable.)
Truth be told, with proper application of redundancy, defence-in-depth and tried-and-tested hardware - I suspect that the commercially-available equipment would provide equal or better reliability than a bespoke unit at a fraction of the cost. Of course, only time would bear that assertion out.
Two fatal accidents later brought AFS ergonomic weaknesses to light.
As an aside, my first ever flight was on a BCAL 1-11. I don't remember much of it however, being only three years old at the time.
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Which are you referring to here?
Autopilot is pilot's helper, it is mindless entity that absolutely can not perform pilot's job! OTOH, if this basic fact was understood around PPRuNe, we'd be poorer for many an excellent (if somewhat unintentional) piece of absurdist humour.
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Don't get automation confused with FBW - two very different things. In fact the automation on the A320 is no more complex than that on your 737NG, which is why automation-related crashes and incidents are comparable in number across all types and manufacturers.
I'm not confusing anything here! So unlike you think I know what I'm talking about! Airbus FBW has some serious issues!
SNPL is completely correct, and I'm not french, don't work for AF or am related to boeing or airbus in any other way then a typerating on my licence.
And yes there are incidents accountable to airbus FBW, SNPL mentioned 4 where it played a factor!
But lets trust in an engineer who never flew any of the aircraft or held command on it.
Last edited by 737Jock; 30th Dec 2012 at 22:23.