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AF 447 Thread No. 11

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AF 447 Thread No. 11

Old 2nd Jul 2013, 13:20
  #201 (permalink)  
 
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Re Femanvate's question - did AF447 change enough to prevent it reoccuring?

When an accident is caused by a large number of negative factors coming together with tragic consequences, I don't believe there is any such thing as the 100% solution. Yes, some of those factors should be a straight forward fix - in particular the pitot tubes which were already a known issue - but those that are related to human behaviour are much more difficult. How do you gaurantee that no pilot will ever haul the nose up to an excessive attitude in response to a fairly simple fault? How do you impress it upon aircraft commanders that leaving the flight deck for a snooze as you are entering one of the most dangerous weather zones on the planet may not be the best idea? How do you ensure that every possible fault scenario has been thoroughly anticipated so that proper procedures and training can be put in place to allow pilots to deal with them effectively and safely? What can you put in place to give relatively inexperienced pilots enough reserve in the tank so that when a challenging situation is presented, their actions aren't detrimental to the result?

These are all very complex questions that don't offer simple solutions. So in other words, while we'd all like to think it can't happen again, how do we know that even if we've dealt with many of the contributing factors, that there aren't others hiding in the weeds, just waiting for the opportunity to strike? For all that we have advanced in aviation equipment, procedures and training, predicitive engineering is still an infant in this game.

Last edited by J.O.; 2nd Jul 2013 at 16:26.
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Old 2nd Jul 2013, 14:06
  #202 (permalink)  
 
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J.O. ‘It’, AF447 should not happen again; as you say there are fixes, and the industry rarely suffers the exact same accident.
Did it change enough for AF447, yes; for future safety, I doubt it.
The critical lesson is how difficult it is to identify the significant contributing factors and the conditions by which these line up – what is significant.

Attributing cause or identifying the ‘holes’ which previously had lined up, suffers hindsight bias.
Humans are biased; it’s easier to blame someone or something than understand the underlying issues. Blame – blame culture, does not help learning.

What the industry might learn is a reminder that accidents can happen from very rare events, and with hindsight there are indicators – precursors, which if understood earlier and managed, might prevent an accident. We cannot succeed in all cases, but we might learn how to prevent the initial events escalating.

Safety is like a boat, they all leak. The art of safety is to identify the large holes, plug them, and ensure that you can bail faster than the residual leaks. But this assumes you understand what is meant by a hole or a significant leak.

We might not be able to identify all aspects, but we could identify and change the process of how ‘holes’ line up; i.e. how we think about safety, anticipate, monitor, respond, and learn; both individually and as an organization.
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Old 2nd Jul 2013, 14:32
  #203 (permalink)  
 
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I tend to agree with Landflap.

And to answer femanvate's question, no, we have not yet learnt these basic lessons to prevent a recurrence of AF447...sadly enough...
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Old 2nd Jul 2013, 16:40
  #204 (permalink)  
 
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I think the real question here is : Why do airlines think it is OK to use less and less experienced pilots?

For example; the sort of pilot who has no experience of "real" aircraft, say turbo prop twins, that they think it is reasonable to hold full back stick/yoke in a stall situation - and they think that by doing so they will recover and fly out of the situation? Or that it's OK to viciously 'pump' the rudder pedals through turbulence, which snaps the fin off.

What is the airline's end-game here?
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Old 2nd Jul 2013, 16:46
  #205 (permalink)  
 
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What is the airline's end-game here?
Possible answer: Getting rid of pilots, since HAL will never go on strike.
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Old 2nd Jul 2013, 17:16
  #206 (permalink)  
 
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Originally Posted by Lonewolf_50 View Post
Possible answer: Getting rid of pilots, since HAL will never go on strike.
If only it were that simple (as I'm sure you're aware!)...

PJ2 has written some excellent posts on the encroachment of the MBA generation into airline management and how it has negatively affected training and safety culture.

http://www.pprune.org/safety-crm-qa-...ml#post3441359
http://www.pprune.org/rumours-news/3...ml#post5256776
http://www.pprune.org/tech-log/48977...ml#post7306229

If people are looking for a thorough and well-reasoned argument, I'd suggest looking them up and starting from there.

And for those thinking of it as an exercise in blaming/exonerating the crew, AF or Airbus - the report makes it clear that mistakes were made by all three of those entities, plus others. In short, none of them come up smelling of roses, and nor does the industry as a whole.

For my part, the old engineering truism:
You can have it done fast, done well or done cheap. Pick two.
rings very true in this case.

Last edited by DozyWannabe; 2nd Jul 2013 at 17:42.
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Old 2nd Jul 2013, 17:29
  #207 (permalink)  
 
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I think the real question here is : Why do airlines think it is OK to use less and less experienced pilots?

For example; the sort of pilot who has no experience of "real" aircraft, say turbo prop twins, that they think it is reasonable to hold full back stick/yoke in a stall situation - and they think that by doing so they will recover and fly out of the situation? Or that it's OK to viciously 'pump' the rudder pedals through turbulence, which snaps the fin off.

What is the airline's end-game here?
In this case the Captain had over 11,000 hours, and the F/O's over 9,000 hours between them. In the case of AA 587 (which I assume you are alluding to) The F/O (PF) had around 4,500 hours including a range of twin turboprop aircraft in his previous employments, (DH6, BE99 and SH360's). The Captain had over 8,000 hours and came from a military background. He had nearly half of his experience as Captain, and had around 6,000 hours with the airline of which over 1,700 were on type.

As is evident from the last 80 years and more, experience hasn't stopped accidents. Technology hasn't stopped accidents. Training hasn't stopped accidents. It is the interaction, development, and understanding of the human factors aspects of how all these things combine together that is leading to huge improvements in safety. It is always going to be a work in progress, and (certainly in my lifetime) never likely to eliminate error or failure.

Training is now moving towards more relevant competency based and specific to the role. It still has a great deal of scope for improvement. Experience is a good thing, but it can also be the façade of bad practice, complacency," normalization of deviance," and weak training and learning.

Airlines are commercial enterprises. They want to offer a regular, safe and profitable commodity. One accident (in many cases) has the potential to kill their business as well as their customers. They don't attract customers, they have no business. They don't offer a regular and safe service, they have no business. They don't make a profit, they have no business. It is really that simple.
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Old 2nd Jul 2013, 17:52
  #208 (permalink)  
 
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Beal - You couldn't be more wrong. First and fore most you can't name ONE accident that experience wouldn't have prevented and does on a daily basis.

Over and over, we see a plane go down and say 'he should have done that' and it's the same old thing, over and over. If they had hired a pilot and not a checklist reader, buddy or a pal, everyone would be alive.
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Old 2nd Jul 2013, 18:16
  #209 (permalink)  
 
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Teldorserious,

If there is any logic in your response, it is so tortured that it is crying out for help. Perhaps you would care to make a sensible statement or question, so that a sensible reply can be offered.
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Old 2nd Jul 2013, 18:19
  #210 (permalink)  
 
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Santa Bárbara Airlines Flight 518 is IMHO an example where a less experienced captain (or even a "magenta line addict") would probably have refrained from taking off with some of the navigation equipment not (yet) working properly. And the Los Rodeos crash is arguably another case where experience and reputation were at least a double-edged sword.
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Old 2nd Jul 2013, 20:39
  #211 (permalink)  
 
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Originally Posted by Armchairflyer View Post
Santa Bárbara Airlines Flight 518 is IMHO an example where a less experienced captain (or even a "magenta line addict") would probably have refrained from taking off with some of the navigation equipment not (yet) working properly.
If I recall correctly, the crew were not aware of the extent to which the nav equipment (even down to the mag compass) was broken.

And the Los Rodeos crash is arguably another case where experience and reputation were at least a double-edged sword.
That was an almost unique situation in that the Captain had spent more time in the simulator as a TRE than he had on the line over the previous months. In the sim, obtaining clearance was usually a formality.

Don't get me wrong - overconfidence is dangerous, and experience *can* sometimes breed overconfidence. However, fundamentally they are two different things. AF447 exposed an industry-wide problem whereby training in several areas - in particular stall recognition/recovery and high-altitude manual handling - had been allowed to slip too far.
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Old 2nd Jul 2013, 21:47
  #212 (permalink)  
 
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And for those thinking of it as an exercise in blaming/exonerating the crew, AF or Airbus - the report makes it clear that mistakes were made by all three of those entities, plus others. In short, none of them come up smelling of roses, and nor does the industry as a whole.
Yes none of them .. included the BEA but they forget to put their mistakes in the report
The phenomenon of ice crystals was officially ignored (was not taken into
account in the regulatory definitions)
Before the accident, the BEA estimated that the number of precursor events had not interest in flight safety.
After the accident, the BEA has undertaken an analysis of the events which led to the issue in emergency (December 2009) a safety recommendation to the certification standards
Pitot probes are changed.
With this recommendation, the BEA has admitted, without saying, that he had erred in its assessment of the facts.
The blockage of the Pitot probes has multiple system failures that seriously affect the control of the aircraft.
This is a serious incident under the European Directive 94/56/EC.
BEA had an obligation to investigate and possibly make recommendations.
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Old 2nd Jul 2013, 21:54
  #213 (permalink)  
 
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@jcj:

By its very own nature the BEA is simply an incident and accident investigation bureau. It is not a regulator and cannot make recommendations unless invited to do so. The previous UAS incidents happened across a wide group of airlines from many countries and none of the investigation bureaus of those countries saw fit to make recommendations either. The revised procedures and workarounds, along with the pitot tube replacement schedule were considered sufficient by all parties at the time, so to point a finger at the BEA in this instance is a fallacy.
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Old 2nd Jul 2013, 22:09
  #214 (permalink)  
 
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It is not a regulator and cannot make recommendations unless invited to do so
The BEA have not to be invited to do investigation on reports of incidents or accidents he know(if those are mandatory for flight safety) and he can made any recommendations he want
Remind your mantra ... the BEA is independent
The regulators are not mandatory to follow those recommendations ... but usually they follow them

none of the investigation bureaus of those countries saw fit to make recommendations either
Pitot icing problems were identified by the BFU (German BEA) since 1999.
Besides Airbus was so aware that it caters to the U.S. FAA
September 2009 in an attempt to make him change the negative formulation for
manufacturer of the AD (see ABI letter to the FAA below):

To:
U.S. Department of Transportation
Docket Operations, M–30
1200 New Jersey Avenue, SE.

West Building Ground Floor
Room W12-140
WASHINGTON, DC 20590, USA
FROM
Marc LE-LOUER
DATE
04 September 2009
PHONE
+33 (0)5 61 93 24 57
FAX
+33 (0)5 61 93 45 80
E-MAIL

OUR REFERENCE
EALA_LR03D09021899
YOUR REFERENCE
Docket Number FAA–2009–0781; Directorate
Identifier 2009–NM–111–AD; Amendment 39–
16004
Copy:
FAA – Vladimir Ulyanov
EASA – L. Gruz
Airbus EA – Y. Régis
Airbus EAL – F. Duclos
Airbus GSE - F. Combes
Subject: Airbus comments on Docket Number FAA–2009–0781; Directorate Identifier
2009–NM–111–AD; Amendment 39–16004; AD 2009–18–08 : Final rule; request for
comments.
Dear Sir,
Airbus is pleased to provide comments on the FAA’s Final rule Docket Number FAA–2009–
0781;
Directorate Identifier 2009–NM–111–AD; Amendment 39–16004; AD 2009–18–08.
In order to be consistent with the EASA text in the AD 2009-0195, we ask you to replace the
sentence " airspeed discrepancies, which could lead to disconnection of the autopilot and/or
autothrust functions, and reversion to flight control alternate law and consequent increased
pilot workload. Depending on the prevailing airplane altitude and weather, this condition, if
not corrected, could result in reduced control of the airplane" in the "Unsafe Condition"
paragraph with the following sentence :
"Airspeed discrepancies may lead in particular to disconnection of the autopilot and/or auto-
thrust functions, and reversion to Flight Control Alternate law. Depending on the prevailing
aéroplane altitude and weather environment, this condition could result in increased difficulty
for the crew to control the aeroplane.
Indeed, from the Handling Quality perspective the unreliable air speed event and the as per
design consequences don't change the a/c contrability. It only increases the pilot workload to
control the a/c.
Secondly could you add the following sentence, which has been inserted in the EASA AD
2009-
0195 (sentence not included initially in the PAD 09-099). It presents the results of additional
Pitot probe tests :
"Preliminary results of additional wind tunnel testing conducted with the C16195BA probe
during
August 2009 are consistent with the qualification data of the probe and have not identified
any safety issue regarding the probe behaviour within the icing envelope as defined in the
appendix

Last edited by jcjeant; 2nd Jul 2013 at 22:21.
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Old 2nd Jul 2013, 22:44
  #215 (permalink)  
 
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Originally Posted by jcjeant View Post
The BEA have not to be invited to do investigation on reports of incidents or accidents he know(if those are mandatory for flight safety) and he can made any recommendations he want
You're wrong there - while the BEA is independent it can only issue reports either if invited to do so, or if the conclusions it comes to vary from those of the designated investigation authority (in the form of a rebuttal).


Pitot icing problems were identified by the BFU (German BEA) since 1999.
Completely different manufacturer and model of tube and a completely different airframe. Pitot tube icing has been a known issue in aviation circles for as long as they've been used!

Besides Airbus was so aware that it caters to the U.S. FAA September 2009 in an attempt to make him change the negative formulation for manufacturer of the AD
Firstly, Airbus has no direct connection to the BEA, DGAC or any other agency of the French government, so I don't see what this has to do with what we were previously discussing.

Secondly, the change in phrasing does not (as far as I can see) downplay the problem in any way - it simply increases the level of technical detail and accuracy (and apparently also ensures that the FAA document is as in-depth as the EASA document).

Last edited by DozyWannabe; 2nd Jul 2013 at 22:46.
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Old 3rd Jul 2013, 00:00
  #216 (permalink)  
 
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while the BEA is independent it can only issue reports either if invited to do so
So .. finally that's a proof that the BEA is not independent ...
You can't be independent if your actions are monitored or must be allowed by somebody else

Last edited by jcjeant; 3rd Jul 2013 at 00:01.
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Old 3rd Jul 2013, 00:17
  #217 (permalink)  
 
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@jcj:

No - "independent" in this case means that the investigating organisation is independent from the regulator and other government agencies, nothing more. The most infamous example of where this became a necessity was following the DC-10 case in the 1970s, where the FAA kept the NTSB at arms' length in favour of the "Gentlemens' Agreement".

Even a nominally independent accident investigation agency does not have the remit to begin an investigation of it's own volition.

Last edited by DozyWannabe; 3rd Jul 2013 at 00:19.
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Old 3rd Jul 2013, 00:59
  #218 (permalink)  
 
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Originally Posted by dozy
while the BEA is independent it can only issue reports either if invited to do so
by who exactly ?
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Old 3rd Jul 2013, 01:53
  #219 (permalink)  
 
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I doubt you need me to tell you that. They are involved by default when an accident or incident occurs to a French-registered aircraft, over French territory or if the aircraft was built in France. In the first and third cases, they are usually guests of the host investigating agency if the accident happened overseas. Sometimes they are called in by other countries' agencies as an independent assessor.

In the case of the previous UAS incidents involving Airbus widebodies, their remit only extended as far as the host nations would allow - and none of them demanded action over and above that which was being done prior to AF447.
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Old 3rd Jul 2013, 03:01
  #220 (permalink)  
 
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Originally Posted by HN39
The captain's "Prend ça" is echoed three times by the PNF. The BEA nor the judicial group of experts understand what "ça" refers to.
That's poor effort regarding an important remark on the cvr especially at a time when full back stick was maintained ...

The next item on the CVR record is the PF saying that he has 'no vario' "there".
Translation is incorrect.
The words are :
  • Je… j'ai, le problème c'est que j'ai plus de vario là
  • The problem is that I don't have any vsi anymore
  • d'accord j'ai plus aucune indication
  • Ok I don't have any indication at all
There's more in it that I don't have a VSI on the standby.

Both the BEA and the judicial experts attribute that to the VSI needle being on the stop, but it has been there (6000 fpm) for some time.
The quotes ?

Therefore I think the PF is replying to the captain and the PNF, who have been pointing to the standby instrument, which doesn't indicate V/S.
Now why would the CPT and PNF point to the standby instruments to use them if all big attitude indicators on the PFDs function and agree ?
What is supposed to be so interesting on the standby that the PFDs have to be ignored ?

Why is it a problem for the PF that he doesn't have V/S? I can understand a pilot needs V/S to maintain altitude or a certain value of V/S. Both pilots have expressed more than once that they've lost control, the altimeter is spooling down rapidly, and the PF announces: "Ï have a problem, it's that I don't have vertical speed indication"?
When indicating, are both V/S in agreement ?
Are 3 altimeters behaving the same way ?
Remember the attitude AoA bank and position of the statics ...
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