AF447 wreckage found
Join Date: Jul 2002
Location: UK
Posts: 3,093
Likes: 0
Received 0 Likes
on
0 Posts
@Petercwelch - I don't think that's a fair question. Going purely on statistics there have been two Boeing airliners (both 757s) that have ended up in the drink due to unreliable air data causing pilots to mishandle the aircraft, whereas to date it has only happened with one Airbus.
The issue at hand is whether the cockpit environment on older airliners is more conducive to help the pilots understand the problem (overcontrol -> stall -> loss of control). Some on here are adamant that it would be the case, others are not so sure.
3 pilots, 6 opinions and all that...
@DC-ATE - you could crash a DC-8 on approach by pulling a single lever too early ("It is forbidden to crash this airplane"). You could disable the takeoff trim warning on a DC-9 just by pulling a single circuit breaker that connected to a bunch of other systems, some of which were on the MEL. You could crash a DC-10 by not closing the door properly, and the door latch design itself would have caused Rube Goldberg (or Heath Robinson to us Brits) to wince. In the latter case, Douglas effectively bribed the FAA to not release that information while promising to fix the problem - they didn't fix it properly and nearly three hundred people died. Don't talk to me about Long Beach's supposedly superior engineering skills - they were riding the coattails of the DC-3's popularity and producing shoddy designs right up until they closed their doors.
The issue at hand is whether the cockpit environment on older airliners is more conducive to help the pilots understand the problem (overcontrol -> stall -> loss of control). Some on here are adamant that it would be the case, others are not so sure.
3 pilots, 6 opinions and all that...
@DC-ATE - you could crash a DC-8 on approach by pulling a single lever too early ("It is forbidden to crash this airplane"). You could disable the takeoff trim warning on a DC-9 just by pulling a single circuit breaker that connected to a bunch of other systems, some of which were on the MEL. You could crash a DC-10 by not closing the door properly, and the door latch design itself would have caused Rube Goldberg (or Heath Robinson to us Brits) to wince. In the latter case, Douglas effectively bribed the FAA to not release that information while promising to fix the problem - they didn't fix it properly and nearly three hundred people died. Don't talk to me about Long Beach's supposedly superior engineering skills - they were riding the coattails of the DC-3's popularity and producing shoddy designs right up until they closed their doors.
Join Date: Sep 2008
Location: MI
Posts: 570
Likes: 0
Received 0 Likes
on
0 Posts
Well.....when I wrote Douglas, I guess I shudda specified DC-8. Never flew the other ones. Didn't like 'em. As to that "lever", it only happened once [which is enough] then everyone knew 'bout it and it never happened again. Give me a yoke any day, not one of these stupid SS controlers.
Join Date: Dec 2007
Location: UK
Posts: 7
Likes: 0
Received 0 Likes
on
0 Posts
But, you'll NEVER get the AB supporters to agree, unfortunately
Petercwelch, #2712,
Your question assumes that the manufacturing design was the primary (dominant) or the only cause. It’s generally accepted that accidents are the culmination of many factors, requiring the interaction of significant issues.
A significant issue in this accident appears to be human behaviour; the crew’s perception and choice of action. Unfortunately we are unable to establish all of the facts of these matters. In our speculation we are exposed to hindsight bias due to the nature and timing of available information.
Some may argue that the Airbus FBW control system design degrades awareness, but the system is used without mishap in everyday operations by Airbus crews.
Have they adapted, have alternative control skills, or use other aspects for awareness? What are these features; were they absent in this accident or did the crew fail to use them? These have yet to be established.
The design of the stall warning system might be similarly cited, but other aircraft, although not engineered in the same way, have similar systems and meet the same requirements – including preventing unwanted warnings in other areas of the flight envelope, e.g. use system inhibits.
A more plausible view is that none of the crew identified the stall condition; again an aspect of awareness, and also, if the all speed displays are unavailable, an aspect which does not appear to differ with aircraft type.
If as suggested in the report, the PF had a mental goal of achieving an erroneous pitch attitude – that required for flight without airspeed, but which did not apply at high altitude, this also is invariant with aircraft type.
Conversely it is arguable that the resultant stall condition could have been recovered with a stick-push system, as fitted to many aircraft – noting that a controlled flight manoeuvre into the stall (as with AF447) would provide similar trim conditions irrespective of aircraft type. But again we can only speculate how the crew might have reacted to a stick push with regard to their mental model of the situation. We would hope that a forced stall recovery would ‘jolt’ the mindset, but evidence from other accidents (Colgan) suggests otherwise.
Many safety activities depend on asking questions, but the key issue is to ask the right question because in most cases, then the answer is obvious.
This accident has posed many questions and the industry is having difficulty in identifying ‘the right one’. This will not involve the aircraft type alone, but include the limits of human performance, the operational situation, organisation, and the system at larger in which we live; it will involve what we do and encounter every day, and how we do it.
Your question assumes that the manufacturing design was the primary (dominant) or the only cause. It’s generally accepted that accidents are the culmination of many factors, requiring the interaction of significant issues.
Accidents arise from the unforeseen and often unforeseeable concatenation (linking) of diverse events, each one necessary, but singularly insufficient. J Reason.
Some may argue that the Airbus FBW control system design degrades awareness, but the system is used without mishap in everyday operations by Airbus crews.
Have they adapted, have alternative control skills, or use other aspects for awareness? What are these features; were they absent in this accident or did the crew fail to use them? These have yet to be established.
The design of the stall warning system might be similarly cited, but other aircraft, although not engineered in the same way, have similar systems and meet the same requirements – including preventing unwanted warnings in other areas of the flight envelope, e.g. use system inhibits.
A more plausible view is that none of the crew identified the stall condition; again an aspect of awareness, and also, if the all speed displays are unavailable, an aspect which does not appear to differ with aircraft type.
If as suggested in the report, the PF had a mental goal of achieving an erroneous pitch attitude – that required for flight without airspeed, but which did not apply at high altitude, this also is invariant with aircraft type.
Conversely it is arguable that the resultant stall condition could have been recovered with a stick-push system, as fitted to many aircraft – noting that a controlled flight manoeuvre into the stall (as with AF447) would provide similar trim conditions irrespective of aircraft type. But again we can only speculate how the crew might have reacted to a stick push with regard to their mental model of the situation. We would hope that a forced stall recovery would ‘jolt’ the mindset, but evidence from other accidents (Colgan) suggests otherwise.
Many safety activities depend on asking questions, but the key issue is to ask the right question because in most cases, then the answer is obvious.
This accident has posed many questions and the industry is having difficulty in identifying ‘the right one’. This will not involve the aircraft type alone, but include the limits of human performance, the operational situation, organisation, and the system at larger in which we live; it will involve what we do and encounter every day, and how we do it.
Join Date: Nov 2009
Location: Somewhere
Posts: 73
Likes: 0
Received 0 Likes
on
0 Posts
while the THS was still moving towards 'full-up,' the PF applied full nosedown for quite a long period; probably because, as the report says, he was (correctly) countering the zoom climb. But the THS just continued on it's 'merry' way to full up
During the transition of the THS there are only a few intermittent nose-down spikes - the trace below the zero line means the stick was held back, pitching up.
Check the elevator trace on the same page: once the THS is on its "merry way to full up", at no time is the elevator pushed to pitch down. Not even close. The best it gets is about 15deg, pitch up. No wonder the THS never came back.
Join Date: Jun 2009
Location: California
Age: 54
Posts: 203
Likes: 0
Received 0 Likes
on
0 Posts
Be very careful with stats especially when comparing apples with oranges.
How many total flight hours were they flown?
What type of flights (any military to theater of operations).
Have you corrected for tech advances - it would be better picking a contemporary of A330.
That said I do believe airbus are in general very safe, sadly the same cannot be said of humans.
How many total flight hours were they flown?
What type of flights (any military to theater of operations).
Have you corrected for tech advances - it would be better picking a contemporary of A330.
That said I do believe airbus are in general very safe, sadly the same cannot be said of humans.
Originally Posted by Dozy
The "Airplane with HAL" :
Number of A330s built : 802
Number of A330 hull losses : 6
Percentage lost : 0.75%
The "Old-fashioned pilot's aircraft" :
Number of DC-10s built : 386
Number of DC-10 hull losses : 31
Percentage lost : 8%
Number of A330s built : 802
Number of A330 hull losses : 6
Percentage lost : 0.75%
The "Old-fashioned pilot's aircraft" :
Number of DC-10s built : 386
Number of DC-10 hull losses : 31
Percentage lost : 8%
Join Date: May 2010
Location: -
Posts: 66
Likes: 0
Received 0 Likes
on
0 Posts
Have you corrected for tech advances - it would be better picking a contemporary of A330.
A330:
Produced 1993–present
Number built 796 as of 30 June 2011
As of June 2011, the Airbus A330 had been involved in thirteen major incidents, including six confirmed hull-loss accidents and two hijackings, for a total of 338 fatalities.
B777:
Produced 1993–present
Number built 923 as of March 2011
As of April 2011, the 777 has been in seven incidents, including one hull-loss accident, and two hijackings, with no fatalities among the passengers or crew.
Any questions still remaining?
Join Date: Aug 2011
Location: Grassy Valley
Posts: 2,074
Likes: 0
Received 0 Likes
on
0 Posts
I think there is very little to be gained by such "comparisons". "margin for Error" has more to say than raw numbers, and it always gets doen to subjective hoorah. both capable ships, and 447 has more to teach us that is real, and precious than fanbase. In a wide field of Gold, the nuggets are gathered early, and eventually, the safety is found in mining.
Dozy;
Sadly unfortunate the example you quote, because it should be a warning to us all. This happened to a very experienced test pilot, at the end of a very busy day. Basic mistakes were made; if it could catch him out, then God help the rest of us. (Don't have the link to the report, but am sure somebody will provide it).
Re; software/hardware anomalies, a few come to mind-(Indian Airlines A320 open descent into ground at (Bangalore); Air Inter A 320 VS/FPA confusion and subsequent descent into ground -already mentioned;(Austria?); Air France A320 low flypast into trees (Paris?); Air Transat 330 fuel leak/crossfeed mishandling anomaly with glide landing into (Azores).
Don't get me wrong; as stated earlier, I am not bashing Airbus; some of these accidents were in the early days of FBW of which Airbus were the pioneers, and good on them. They are truly innovators. But there is no denying that their systems are not easy to understand, and they did make changes after each of these accidents. But then so did Boeing, and they have been in the business a lot longer.
Not wishing to sound facetious, but would you care to provide examples of where this has been the case any later than, say, 1994 (when the death of senior test pilot Nick Warner on a demonstration flight caused them to re-examine their priorites)?
Re; software/hardware anomalies, a few come to mind-(Indian Airlines A320 open descent into ground at (Bangalore); Air Inter A 320 VS/FPA confusion and subsequent descent into ground -already mentioned;(Austria?); Air France A320 low flypast into trees (Paris?); Air Transat 330 fuel leak/crossfeed mishandling anomaly with glide landing into (Azores).
Don't get me wrong; as stated earlier, I am not bashing Airbus; some of these accidents were in the early days of FBW of which Airbus were the pioneers, and good on them. They are truly innovators. But there is no denying that their systems are not easy to understand, and they did make changes after each of these accidents. But then so did Boeing, and they have been in the business a lot longer.
Join Date: Jul 2002
Location: UK
Posts: 3,093
Likes: 0
Received 0 Likes
on
0 Posts
@xcitation : I'm stepping back for a bit, but quickly in answer to your question - I'm well aware of "lies, damned lies and statistics", and was just trying to illustrate the point that "the good old days" weren't all that good in some respects
@ap07, I'm not interested in Airbus vs. Boeing discussions - I was simply trying to prove the adage that things have gotten safer thanks to advances made by Airbus, Boeing and *all* manufacturers. Although it's worth noting that of the six A330 hull losses, 2 were due to military action and one was due to a cargo-handling accident. Of the three that were related to flight, one was the infamous test flight, another was the Libyan A330 which so far has no technical cause and the third is AF447.
In any case these statistics are too small to make a valid comparision, mercifully.
@Phantom Driver, the Indian incident, Air Inter and Nick Warner's A330 crash were largely put down to mode confusion, which has since been rectified. Air Transat was down to a maintenance issue IIRC and Habsheim (the A320 lumberjack) is a whole other story, which largely comes down to atrocious preparation on the part of AF, followed by a sequence of bad judgement calls made by the captain. Of these, only Air Transat happened after 1994.
@SLFinAZ below : How have "'A' ... also single handedly pushed the average pilot skill level significantly lower"? I'm all ears. Glass cockpits and full-featured FMS autopilots were pioneered by the A300, but enthusiastically picked up by Boeing with the 757 and 767, and Douglas with the MD-11. "What's it doing now?" has never related to FBW, but to the FMS/FMC/autopilot (call it what you will), which were well-established for more than a decade before the A320 first flew. And as for in-flight hull-loss stats, A330 vs B777 is currently 3:1 (not 0, as you stated), but again these numbers are too small to make a statistical comparison.
@ap07, I'm not interested in Airbus vs. Boeing discussions - I was simply trying to prove the adage that things have gotten safer thanks to advances made by Airbus, Boeing and *all* manufacturers. Although it's worth noting that of the six A330 hull losses, 2 were due to military action and one was due to a cargo-handling accident. Of the three that were related to flight, one was the infamous test flight, another was the Libyan A330 which so far has no technical cause and the third is AF447.
In any case these statistics are too small to make a valid comparision, mercifully.
@Phantom Driver, the Indian incident, Air Inter and Nick Warner's A330 crash were largely put down to mode confusion, which has since been rectified. Air Transat was down to a maintenance issue IIRC and Habsheim (the A320 lumberjack) is a whole other story, which largely comes down to atrocious preparation on the part of AF, followed by a sequence of bad judgement calls made by the captain. Of these, only Air Transat happened after 1994.
@SLFinAZ below : How have "'A' ... also single handedly pushed the average pilot skill level significantly lower"? I'm all ears. Glass cockpits and full-featured FMS autopilots were pioneered by the A300, but enthusiastically picked up by Boeing with the 757 and 767, and Douglas with the MD-11. "What's it doing now?" has never related to FBW, but to the FMS/FMC/autopilot (call it what you will), which were well-established for more than a decade before the A320 first flew. And as for in-flight hull-loss stats, A330 vs B777 is currently 3:1 (not 0, as you stated), but again these numbers are too small to make a statistical comparison.
Last edited by DozyWannabe; 7th Aug 2011 at 20:52.
Join Date: Mar 2009
Location: Phoenix, AZ USA
Age: 66
Posts: 0
Likes: 0
Received 0 Likes
on
0 Posts
Actually I think that "A vs B" is still not only a very valid question but lies at the heart of the matter.
From my perspective at this point "A" is a safer airplane in the hands of a less qualified pilot. I do not believe that "B" has any inherent advantage with a truly qualified aviator at the controls ("Skullyish")....with the caviat that even with a very seasoned pilot with an above average professional level understanding of the FBW system it is possible for him to have a "what is it doing now" moment.
The real issue is that while "A" has without a doubt single handedly pushed the envelope of what is technologically possible...they have also single handedly pushed the average pilot skill level significantly lower. Regardless of the number of representative hull losses (which could be much worse for the 320/330) {vs 777} the reality is that its B = 0 and A = to many.
What AF447 has made abundantly clear is training/CRM standards (in at least one major carrier) have degraded to a point where if the "system" can't save the plane we have no assurance the pilot will be able to. At the end of the day this crash will boil down to 100% pilot error IMO.
From my perspective at this point "A" is a safer airplane in the hands of a less qualified pilot. I do not believe that "B" has any inherent advantage with a truly qualified aviator at the controls ("Skullyish")....with the caviat that even with a very seasoned pilot with an above average professional level understanding of the FBW system it is possible for him to have a "what is it doing now" moment.
The real issue is that while "A" has without a doubt single handedly pushed the envelope of what is technologically possible...they have also single handedly pushed the average pilot skill level significantly lower. Regardless of the number of representative hull losses (which could be much worse for the 320/330) {vs 777} the reality is that its B = 0 and A = to many.
What AF447 has made abundantly clear is training/CRM standards (in at least one major carrier) have degraded to a point where if the "system" can't save the plane we have no assurance the pilot will be able to. At the end of the day this crash will boil down to 100% pilot error IMO.
Join Date: Jun 2010
Location: asdf
Posts: 100
Likes: 0
Received 0 Likes
on
0 Posts
Stop putting aeroperu and birgenair as examples of anything.
They have no comParison whatsoever to af447 and if they crashed was to reasons totally unrelated to the systems of the planes.
Its very clear the bea and airbus want to send the same message regarding af447, the thing is that is not at all clear.
They have no comParison whatsoever to af447 and if they crashed was to reasons totally unrelated to the systems of the planes.
Its very clear the bea and airbus want to send the same message regarding af447, the thing is that is not at all clear.
Join Date: Nov 2009
Location: Somewhere
Posts: 73
Likes: 0
Received 0 Likes
on
0 Posts
Yes please, can you list those 6 hull losses?
Interface/scan/human factors
This discussion has been largely focussed on the central and tragic sustained pitch-up; may I request attention to a possible clue which not all have picked up? Please take another look at the roll axis traces (bottom of pp 29, 30 of report 3). (I am grateful to xcitation et al. for their posts yesterday which made me revisit in more detail my bad gut feelings on first viewing these traces).
1. I'd expect anyone having the aircraft unexpectedly dumped in his lap on AP disconnect to take a few moments to 'get hold of her'. It took the PF ~ 35 seconds to control the roll, and in that period I see what looks to me like overcontol and PIO; the oscillations are too regular for this to be attributable just to (midocean) turbulence. In this period he seems to be struggling more that I would expect of a fully fit and current-on-type pilot; am I being unfair?
2. During this 35 second period I surmise that the PF's attention was focussed strongly or exclusively on his display re. roll - which was evidently working perfectly well - to the possible exclusion of a better scan.
The PNF starts very rightly to 'nag' towards the end of this period, and what happens afterwards seems to me uncannily like what instructors recognise as 'freeze' when a student is unintentionally overloaded. (My compliments to BEA for their very helpful combination of CVR and FDR events).
I am neither willing nor able to seek to apportion any blame - I have never flown a sidestick aircraft, nor indeed any without the 'luxury' of tactile feedback on the controls - can Airbus drivers please comment on the significance or otherwise of the early roll-axis traces?
1. I'd expect anyone having the aircraft unexpectedly dumped in his lap on AP disconnect to take a few moments to 'get hold of her'. It took the PF ~ 35 seconds to control the roll, and in that period I see what looks to me like overcontol and PIO; the oscillations are too regular for this to be attributable just to (midocean) turbulence. In this period he seems to be struggling more that I would expect of a fully fit and current-on-type pilot; am I being unfair?
2. During this 35 second period I surmise that the PF's attention was focussed strongly or exclusively on his display re. roll - which was evidently working perfectly well - to the possible exclusion of a better scan.
The PNF starts very rightly to 'nag' towards the end of this period, and what happens afterwards seems to me uncannily like what instructors recognise as 'freeze' when a student is unintentionally overloaded. (My compliments to BEA for their very helpful combination of CVR and FDR events).
I am neither willing nor able to seek to apportion any blame - I have never flown a sidestick aircraft, nor indeed any without the 'luxury' of tactile feedback on the controls - can Airbus drivers please comment on the significance or otherwise of the early roll-axis traces?
Join Date: Jan 2005
Location: W of 30W
Posts: 1,916
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by takata
Well who cares what I'm doing for a living.
SIDE STICK INDICATION ON PFD IN FLIGHT :
Another gadget that would require direct visual attention.
Don't you think AF crew had already too many direct visual things to look at ?
Nothing like fully visible yokes, visible by all, and so, without direct visual attention.
But you don't have to trust me. Still, I'm talking by experience ... what about you ?
Originally Posted by takata
In fact, because nobody using those aircraft seems to be very concerned about such an "obvious" need or it would have been made possible from two decades.
See earlier reply.
Originally Posted by takata
On the other hand, you just hate this brand, whatever their reasons being to do it like that. I can't remember a single feature you actually liked about an aircraft you are supposed to fly. On my side, I'd like to know why is your grief so deep? Personnal vendetta?
I'm sure you'd be better talk about the FDR data you like to claim as "NORMAL"
Join Date: Jun 2009
Location: Paris
Posts: 691
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Jazz Hands
Other than the test-flight at Toulouse, two Sri Lankan A330s were shot up at Colombo airport, a Malaysian A330 was written off by a chemical spill, and the loss of AF447 and Afriqiyah 771 makes six.
Hence, as the original poster was talking about "air transport safety related to type", and not about insurances fees, it looks to me that war actions are irrelevant (or any terrorism/criminal act), as well as cargo hazards on the ground/ maintenance issues or manufacturer test flight programs (same for the long list of supposed "major accident").
Hence, one won't refrain from increasing by 200% those (statistically) close to zero figures in order to scary as many people as possible.
The reality is that, hopefully, there was only two operational transport losses : AF447 and Afriqiyah 771, none of which, so far, revealed a potential tendency of the type to fall from the sky per dozens in the close future, while it did not also during the last 20 years.
Originally Posted by SLFinAZ
Regardless of the number of representative hull losses (which could be much worse for the 320/330) {vs 777} the reality is that its B = 0 and A = to many.
Concerning your proposal, why not adding all Airbus (A300 + 310 + 320 + 330 + 340 + 380) for comparing them vs. B777 exceptional service records inside the entire Boeing fleet?
I'm sure that your point will be even more telling about the danger of boarding such an Euromade flying garbage. Most of you guys, are sounding like your worst press makers each time an Airbus is lost; whatever the reason, the question of the type "safety" will be raised first, even before a single fact would be established concerning the circumstances.
Today, I don't find this obvious behavior anymore chocking but quite succesful after reading occasionnally a couple of post from here. There is no more objectivity remaining concerning such matters and our lawyers are the only one to win, everytime, at this little game.
Nonetheless, I can also predict that Airbuses accident statistics will increase in the future, until we'll run out of gas, as their share of the skies is also increasing daily. Consequently, it's everyone interest - pilots, crews and passenger - to stick more to the facts rather than pre-digested opinions.
