As HN39 has mentioned, the likelihood of ice crystals above FL300 and less than -40 deg C wasn't considered.
The following proposed amendment is the outcome of more recent UAS events. http://oi42.tinypic.com/2yjvbc3.jpg |
I still remain to be convinced by the man/machine interface explanation. We are running the danger of over-generalising from one specific example. Nothing points to a problem with the interface - rather it consistently points to a failure of crew performance. There was and still is a procedure for UAS which if followed clears the incident up quite effectively. Other crews have successfully dealt with the issue so why didn't this one? What was the difference that caused this crew to stall and crash their aircraft?
This is the issue which all attempts to blame the machine fail to address. Why this crew? What was so different about them that they couldn't follow the SOPs, that CRM was non-existant and that there was no clear chain of command? The interface is not the issue because other crews handled it successfully. Training and culture can also be added to the mix but it also and significantly comes down to the individual members of the crew and does not go beyond them. Certainly the aircraft and the controls can probably be re-designed so that this sort of incident would never happen again and I would favour this but I can't help suspecting that without better training someone will find another way to crash one of these aircraft. |
Hi,
Why this crew? What was so different about them that they couldn't follow the SOPs, that CRM was non-existant and that there was no clear chain of command? Have a incompetent pilot in a crew can happen Have two incompetent pilots in a crew is rare Have three incompetent pilots in a crew defies statistics |
Originally Posted by mm43
As HN39 has mentioned, the likelihood of ice crystals above FL300 and less than -40 deg C wasn't considered.
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CONF's experience sounds like he ended up in Direct Law or Abnormal Attitude, as Alternate in any mode should still have autotrim enabled.
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@mm43,
Hi,
Originally Posted by mm43
@DiagnosticThanks for your well thought-out post.
Originally Posted by mm43
That "step beyond" was an attempt to stop the initial "misunderstanding" and/or "startle factor" that has previously been discussed. It may be viewed as problematic to an outcome, but we are currently dealing with an outcome that became a "problem".;)
My specific concern is that if such automated UAS handling is introduced, then the (a) recognition of UAS and (b) subsequent actions, have got to be correct. :) I just don't know whether the level of confidence in the automation is there yet (and the pilot/passenger confidence in the automation!), to make this option (i.e. an automated UAS response) better than leaving the human in the loop (i.e. a guided UAS response / warning). I'm very happy to read the views of the experts in this area. The option I am most concerned about, is leaving the situation as it is, due to the inadequate UAS recognition and handling by the other crews (in addition to AF447) as highlighted in the BEA Interim Report 2. While this was only one hole in the AF447 "swiss cheese", if that hole can be closed (or at least made smaller), in a (relatively) low cost / low risk way, then surely we reduce the risk of all the holes lining-up again. @Old Carthusian, Hi,
Originally Posted by Old Carthusian
I still remain to be convinced by the man/machine interface explanation. We are running the danger of over-generalising from one specific example.
To use your words: I "remain to be convinced" that, had the AF447 crew truly realised that the "lost speeds" (to quote the PNF) were actually expected due to a temporary UAS, would any of the subsequent events leading to the crash have happened? Reduce the "startle factor", reduce the crew's concern that this is an unusual problem, remind them to turn off the FD etc. - does the PF then follow whatever (unfortunately unknown) cues he did, which caused the "zoom climb"? Perhaps not. I'm not trying to convince you that I'm "correct", but over some decades working with diagnosing complex systems, I have seen many many times, that having an incorrect mental model of what is happening at the beginning of a problem drastically reduces the liklihood of correct handling (especially quick & efficient handling), as that problem continues. It's from that experience, that I see similarities with the sequence of events on AF447.
Originally Posted by Old Carthusian
Nothing points to a problem with the interface - rather it consistently points to a failure of crew performance.
Originally Posted by Old Carthusian
Other crews have successfully dealt with the issue so why didn't this one?
Originally Posted by Old Carthusian
This is the issue which all attempts to blame the machine fail to address. Why this crew?
Originally Posted by Old Carthusian
What was so different about them that they couldn't follow the SOPs, that CRM was non-existant and that there was no clear chain of command?
Originally Posted by Old Carthusian
The interface is not the issue because other crews handled it successfully.
Originally Posted by Old Carthusian
Training and culture can also be added to the mix
Originally Posted by Old Carthusian
but it also and significantly comes down to the individual members of the crew and does not go beyond them.
|
Originally Posted by DozyWannabe
CONF's experience sounds like he ended up in Direct Law or Abnormal Attitude, as Alternate in any mode should still have autotrim enabled.
|
the inadequate UAS recognition and handling by the other crews (in addition to AF447) as highlighted in the BEA Interim Report 2. The BEA Interim Report 2 makes it clear (at least to me) that there is a much larger problem with UAS recognition & handling if several crew's behaviour was wrong (which is a documented fact) Several other crews did not recognise & handle UAS correctly. Are you really OK with that, as long as they don't crash on that specific time they mis-handle it? |
Hello Diagnostic;
Enjoying reading your contributions, thank you. If I may offer a thought and a comment on the points of discussion between you and Old Carthusian... On an increase in automated responses, I can understand the logic of such an argument (the BUSS relies upon this logic), but what concerns me from a pilot's p.o.v. is long-term reduced situational awareness and the need for in-depth understanding of high-altitude, high-Mach No. swept-wing flight, (old fashioned "airmanship", I guess) because it is still humans who are doing the piloting. I offer this view out of a concern for what remains inexplicable, and that is the instant decision to pitch a transport aircraft up at such high pitch-rates (increasing 'g'-loading to 1.55g) to such high pitch attitudes and keep the aircraft there. I would be interested in either data or an argument that this indicates an interface problem, for, as you are, I am open to any information that shows that normal training and SOPs for this event are inadequate in some circumstances and because of obscurity are best left to automated responses. As has been observed throughout the thread by those who fly these aircraft, such pitch attitudes at cruise altitudes are simply never intentionally achieved for the very reasons loss of control occurred. In re your observation, "Several other crews did not recognise & handle UAS correctly.", I don't recall specifically where there were untoward outcomes due recognition and handling issues with other crews in other events but again am open to new information. There are no characterizations one way or the other in IR2 [Interim Report 2], Appendix 7 regarding crew responses one way or another and from what I've read I don't see any descriptions of difficulties experienced by other crews in the body of IR2. There were a few events such as the Air Caraibes, (report here, in French), the Northwest and the TAM events but to my recollection, (and I have been wrong on more than a few things before!), the UAS events haven't been problematic as most crews "did nothing" and the airspeed returned within a minute or less. The argument here isn't at the stage of deciding whether more automation, the same level of automation or reduced interventions are needed. This is very much a continuing dialogue between pilots and engineers! The ability to "look through" the automation and decide for oneself what the airplane is doing, what it needs and why, is being lost because it is being supplemented and when supplements occur, practice and therefore skill, then thinking and knowing atrophy I have had kindly pointed out to me a recent conference at the Royal Aeronautical Society entitled, "The Aircraft Commander in the 21rst Century". There is an excellent videoed presentation from this conference by Captain Scott Martin, (Gulfstream Experimental Test Pilot) on the very topic at hand. From the site: In this exclusive video from the conference, Captain Scott Martin, Experimental Test Pilot at Gulfstream Aerospace talks us through the evolution of the flight deck and how Gulfstream manages to balance the role of automation with providing easily accessible information for the pilot. He also discusses key issues for future flightdeck design in integrating information technology and computers into aircraft and how this ‘second revolution’ in human flight not only affects the military and airline pilot, but also the GA and private flyer. Additionally he talks about the expectations of the next generation of pilots in dealing with these glass cockpits and recommendations in designing the human-machine interface. |
Originally Posted by CONF iture
(Post 7119505)
If it was Direct Law the USE MAN PITCH TRIM PFD MSG would have show up ...
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HazelNuts39 wrote:
Not all UAS scenarios are as obvious as AF447. The high altitude / ice particle scenario is a relatively recent addition to the family. |
Originally Posted by DozyWannabe
As effective PF during our experiments, I was relying on the TRE to watch ECAM as my concentration was 100% on the PFD, SS and trim wheel. I'd be impressed if you could read ECAM while trying to maintain what they were doing.
|
rgbrock1;
Quote: Not all UAS scenarios are as obvious as AF447. The high altitude / ice particle scenario is a relatively recent addition to the family. Why? Surely aircraft have been flying at such altitudes for quite some time now. What has changed? 5th Apr 2012 11:57 I've thought of that often - what if we had lost all speed indications? There were no pitch-power tables at the time but we could have used the FOM Long-range cruise numbers to keep us safe and monitored pitch, comparing it with past experience. We'd have probably continued; it was night, winter conditions at departure - destination was daylight and a bit warmer. I doubt if ours was the only such experience. The difficulty with automation is GIGO - if the info isn't available to the flight crew, what's the automation using? The notion of "historical figures" has been broached, (as in, what's the airplane been doing over the past ten minutes") but that's what pilots do anyway, and supplementing such awareness gradually destroys such awareness. A few have hit upon a very good point - if we fix this, then what will be the next cause? Or do we teach airmanship sufficiently to keep the aircraft safe? While cadet programs teach technical competence, do they teach one how to be "a pilot"? |
Originally Posted by CONF iture
(Post 7119986)
Good ... USE MAN PITCH TRIM PFD MSG
|
Originally Posted by DozyWannabe
(Post 7119489)
CONF's experience sounds like he ended up in Direct Law or Abnormal Attitude, as Alternate in any mode should still have autotrim enabled.
I don't think the SIM would replicate the fall in measured airspeed at the pitots at high AOA and fail all ADRs as a result. |
The high altitude / ice particle scenario is a relatively recent … What has changed?
Some thoughts;-
http://icingalliance.org/meetings/RI...ersion_nss.pdf IASCC - International Air Safety & Climate Change conference - presentations, workshop 1, day 2, Eric Duvivier, EASA - "High Altitude Icing Environment" http://www.ukfsc.co.uk/files/Safety%...Oct%202009.pdf |
Hi PJ2,
Thanks very much for your comments all through these threads, and for the opportunity to discuss. I've tried to minimise the quotes, while still (hopefully) keeping the context - if you feel this has distorted things, then sorry & please correct me.
Originally Posted by PJ2
On an increase in automated responses, I can understand the logic of such an argument (the BUSS relies upon this logic), but what concerns me from a pilot's p.o.v. is long-term reduced situational awareness and the need for in-depth understanding of high-altitude, high-Mach No. swept-wing flight, (old fashioned "airmanship", I guess) because it is still humans who are doing the piloting.
After all, if there is an engine fire, the systems (I don't know if it's the FADEC or others) detect the excessive temperature and alert you, as the pilot, to that specific problem. (I flew several of these in a B737 simulator, some years ago - that bell gets the heart racing :) ). The system does not just say "Hey, something is wrong - I know what the problem is, but you have to work it out from some gauges on the panel - and hurry up!". Why give the crew a specific fire warning (or low fuel warning, or any of the other warnings where the system highlights the specific issue), and not give the crew a specific UAS warning? In your B767 example a few posts ago, is it sensible (and optimal) to make the crew "jump through the mental hoops" to try to work backwards from the "Rudder ratio" EICAS caution, to the underlying UAS event?
Originally Posted by PJ2
I offer this view out of a concern for what remains inexplicable, and that is the instant decision to pitch a transport aircraft up at such high pitch-rates (increasing 'g'-loading to 1.55g) to such high pitch attitudes and keep the aircraft there.
However, if the PF had correctly announced and followed the UAS procedure, then they would both have been focussed on the 5 degree pitch target instead, wouldn't they - at least possibly?
Originally Posted by PJ2
I would be interested in either data or an argument that this indicates an interface problem, for, as you are, I am open to any information that shows that normal training and SOPs for this event are inadequate in some circumstances and because of obscurity are best left to automated responses.
a) too difficult to recognise UAS via the existing interface, or/and b) insufficient training to recognise UAS via the existing interface. IMHO these are related - the less obvious the interface to report a UAS (and to also encourage that the UAS procedure should be followed) to the crew, the more training, skill, concentration, ongoing crew practice will be needed. Or do you have a different view? More details below...
Originally Posted by PJ2
In re your observation, "Several other crews did not recognise & handle UAS correctly.", I don't recall specifically where there were untoward outcomes due recognition and handling issues with other crews in other events but again am open to new information.
Originally Posted by PJ2
[...] to my recollection, (and I have been wrong on more than a few things before!), the UAS events haven't been problematic as most crews "did nothing" and the airspeed returned within a minute or less.
As I understand it, one of the reasons for crew procedures is precisely to prevent different outcomes depending on crew, time of day, visibility, and all the other variables which a crew has to deal with. Once we see lack of adherance to procedures, don't we get closer to the chances of "bad things" happening? That has been my experience, both with flying and with other highly-controlled situations. Of the 13 UAS events where the BEA had sufficient detail to know what the crew did / did not do: "Four crews did not identify an unreliable airspeed" and "For the cases studied [which I interpret as being all 13 cases] the recording of the flight parameters and the crew testimony do not suggest application of the memory items in the unreliable airspeed procedure: * The reappearance of the flight directors suggests that there were no disconnection actions on the FCU; * The duration of the engagement of the Thrust Lock function indicates that there was no rapid autothrust disconnection actions then manual adjustment on the thrust to the recommended thrust; * There was no search for display of an attitude of 5°." So as I read it, all 13 crews "got it wrong", to a greater or lesser extent, with a third of them (4 out of 13) failing to do any UAS procedure, and all 13 failing to do the memory items. Isn't that just a timebomb waiting for a crew getting things badly wrong in the future, when they are presented with an unrecognised UAS at the "wrong time" (sleepy, poor CRM, "startle factor" etc.)? If they get distracted trying to diagnose a non-existant instrument fault (which is really just temporary UAS), couldn't that potentially lead to another AF447-like event? IMHO, based on reading other accident reports where distraction was a factor - yes.
Originally Posted by PJ2
The ability to "look through" the automation and decide for oneself what the airplane is doing, what it needs and why, is being lost because it is being supplemented and when supplements occur, practice and therefore skill, then thinking and knowing atrophy
However, are you saying that aircraft system designers shouldn't help flight crew by giving an explicit warning for UAS, even though the systems know that there is "just" a UAS event (which has a procedure to follow) and not some other instrumentation fault (which needs to be investigated, diagnosed, coped with, etc.)? I have a view about how an automated response might be considered, in a way that still keeps the crew "in the loop", but I'd like to initially focus on giving explicit UAS warnings (to try to drive the following of UAS procedures).
Originally Posted by PJ2
I have had kindly pointed out to me a recent conference at the Royal Aeronautical Society entitled, "The Aircraft Commander in the 21rst Century". There is an excellent videoed presentation from this conference by Captain Scott Martin, (Gulfstream Experimental Test Pilot) on the very topic at hand.
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@Hamburt Spinkleman,
Hi,
Originally Posted by Hamburt Spinkleman
Inadequate, wrong, mis-handle, in-correct. What in report No. 2 do you see that warrants those terms?
Or do you see this part of the BEA report as showing correct UAS procedures were followed in all 13 cases? Or were completely followed in even one case? |
Diagnostic
I am afraid we are still faced with the question of why? It does still come down to the individual crew. It is something that I learned flying replica biplanes (note that I have never flown big transport aircraft but I feel what I learned has some relevance). - know your machine. Know your drills. There is no escape from this. The crews who didn't initially recognise UAS were still able to successfully deal with the problem. One crew (AF447) wasn't and followed a totally inappropriate behaviour pattern. Evidence indicates that the safeguards expected in a transport aircraft were not utilised but were for some reason ignored. This is, I am afraid, a crew issue - not a machine issue. It also relates to this particular crew not the others. I would suggest that reading some of the Korean Airlines accident reports would be productive. They are different accidents but the cultural parallels and CRM failures are instructive and one can see a bearing on this accident. We have to be very careful in trying to find a 'hard' solution when the cause may well lie in the 'soft' factors. |
@Old Carthusian,
Hi, As with my reply to PJ2 I've tried to reduce the quotes a little, but if you think I've destroyed the context, then I'm sorry and please point out what's wrong.
Originally Posted by Old Carthusian
I am afraid we are still faced with the question of why?
Originally Posted by Old Carthusian
It does still come down to the individual crew.
Originally Posted by Old Carthusian
It is something that I learned flying replica biplanes (note that I have never flown big transport aircraft but I feel what I learned has some relevance). - know your machine. Know your drills. There is no escape from this.
Originally Posted by Old Carthusian
The crews who didn't initially recognise UAS were still able to successfully deal with the problem.
Originally Posted by Old Carthusian
One crew (AF447) wasn't and followed a totally inappropriate behaviour pattern.
Originally Posted by Old Carthusian
Evidence indicates that the safeguards expected in a transport aircraft were not utilised but were for some reason ignored. This is, I am afraid, a crew issue - not a machine issue.
To suggest that this is (only) a crew issue implies that you believe the machine is perfect. And yet a UAS situation was reportedly not identified at all by 4 out of 13 other crews. Don't you think that might be pointing to it being too difficult for typical crews to reliably recognise a UAS, using the current recognition method being taught?
Originally Posted by Old Carthusian
It also relates to this particular crew not the others.
Originally Posted by Old Carthusian
We have to be very careful in trying to find a 'hard' solution when the cause may well lie in the 'soft' factors.
I'm suggesting that it is possible to mitigate some inevitable "soft" (i.e. human) factors (e.g. no human is perfect; we all have circadian rhythms & limited attention spans etc. etc.) by improving some systems behaviours, to better support the pilots when things go wrong (i.e. tell them clearly about a UAS event - don't leave them to work it out from hints). That is in addition, of course, to extra training, more hand-flying for the crews etc. etc. |
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