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AF 447 Thread No. 9

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AF 447 Thread No. 9

Old 6th Jul 2012, 01:34
  #61 (permalink)  
 
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Appendices

gums

Try the annexes au rapport final area at the bea site...
Rapport final

Last edited by LandIT; 6th Jul 2012 at 01:35.
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Old 6th Jul 2012, 01:37
  #62 (permalink)  
 
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"the lack of understanding of what the aircraft was doing"

Hi,

MountainBear:



What I do not comprehend is why they did not comprehend.


A good machine is transparent. You ALWAYS control it. Through a constant comprehension.

???
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Old 6th Jul 2012, 01:40
  #63 (permalink)  
 
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First off congratulations to the French institutions for their endeavours in retrieving the evidence and the subsequent analysis. Irrespective of sidesticks and yokes, aoa indicators , huds or other technical options, the fate of this aircraft was a consequence of the actions of 3 human beings over a 4 minute interval in their otherwise peaceful lives. No machine can be perfect so its an equation of competence, training, knowledge and readiness.
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Old 6th Jul 2012, 02:10
  #64 (permalink)  
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a tremendous amount of basic flying skills are no longer required to be taught.

.. while the automatics are working ... which is why my old slide rule still sits in the bottom drawer (not that I would like to have to demonstrate my residual competence on the beast at a moment's notice).

Through a constant comprehension.

.. and apprehension ...

No machine can be perfect so its an equation of competence, training, knowledge and readiness.

.. not a bad summation.

Clearly there has to be a point beyond which diminishing returns makes additional training investment a moot point and not rationally justifiable .. however, establishing just where that point might reside depends a lot on what coloured glasses the viewer is using.

I have noted, in a variety of test circumstances, that a characteristic of the experienced pilot is a tenacious devotion to achieving the goal. This admirable trait is defeated if we don't give him/her a fighting last ditch chance to save the day when all the gee-whizz stuff takes a holiday.
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Old 6th Jul 2012, 02:21
  #65 (permalink)  
 
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Thanks IT, got the full CVR appendix and others.

As many here expected, a combination of training, CRM, and the control law reversions/displays all played a role in the tragedy.

I shall cut the crew a bit of slack. Not a helluva lot, but I have to look at their experience and previous training. And then there's the belief by a few that the "system" will take care of them.

I shall not cut the FBW mechanization a single atom of slack, nor the associated lack of clear displays to the crew as to what they had available ( so-called protections) nor basic steering guidance for the crew that had thousands of hours using the AP and not actually flying the jet. Don't mean to be harsh, but it's what I feel.

This will be a landmark accident report in terms of recommendations and findings and.....

My prayers are that we shall see improved training, improved CRM and maybe some changes in the reversion sequences of the FBW systems when the air data sensors fail.
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Old 6th Jul 2012, 03:11
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Well done, Gums. (We're all bz reading...)

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Old 6th Jul 2012, 03:13
  #67 (permalink)  
 
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I read the final report and much of what was discussed in these pages is there.

My only nit is that there is no discussion that the crew seems not to have been aware of or concerned about altitude until the 10,000s digit dropped off the altitude display, i.e. went from 5 digits to 4:

2 h 13 min 31,7 PF (*) au niveau cent -- FL 100
2 h 14 min 07,3
PNF je cabre PF ben il faudrait on est à quatre mille pieds
PNF I'm pitching up PF Well we need to we are at four thousand feet

and while recovery from 4000' would have been unlikely even then they did not think of stall.

Earlier on we have PF:

2 h 11 min 58,2 Je… j’ai, le problème
2 h 11 min 58,6 c’est que j’ai plus de vario là

who feels he has lost VS indication.

Perhaps if the VS pointer was red, thick and flashing it may have clued in the crew in time.

Last edited by RatherBeFlying; 6th Jul 2012 at 03:37.
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Old 6th Jul 2012, 03:16
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Changes made by Air France - post accident

5.1.2 Modifications to reference systems
  • Documentation
    • Changeover to manufacturer’s documentation in English. The B777 division will be the first to be thus equipped in October 2012.
An interesting decision, but confirming a common language policy and easy comparison with similar documentation worldwide. IMO to be applauded.
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Old 6th Jul 2012, 05:23
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I keep reading the "• Appendix 1 CVR Transcript" because I think it does speak volumes about the mind set of the crew. I still think that humans factors were the main cause of this crash. There is a lot of paper work that contributes to diverge the attention of the crew from flying the airplane. CRM was no where to be found that night. How do you get a Cessna pilots license without knowing what Stall means? Who cares about over speed when altitude keeps dropping? 25,000 feet (actually 28,000) were casually lost at level 100 and keeping the wings level was more important? ...?

Anyways, it is over for now until the next one.
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Old 6th Jul 2012, 06:30
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I still think that humans factors were the main cause of this crash.
Yes, and just humans. The sad thing is, if at the first sign of anything going wrong, they'd all trooped out of the cockpit, sat down, had a coffee and a croissant and come back to their seats five minutes later, they'd probably still be alive to talk about it.
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Old 6th Jul 2012, 08:03
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Something in the CVR transcript I have not seen til now... Very late in the text.

2:13:53.0. Page 31 CVR transcript (English)

Captain: "So wait...AP off". (sound of selector button....)

Que?

Last edited by Lyman; 6th Jul 2012 at 08:12.
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Old 6th Jul 2012, 08:17
  #72 (permalink)  
 
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RR DNB:

UAS IMMEDIATE DETECTION

Quote:
it is impossible.
It is POSSIBLE AND EASY! (Simple engineering solution)*

(*) Will brief on that important issue in Man machine interface Thread
I would suggest you apply for a job within AIB.

IMO the most sensible solution:





To not understand - the AIRBII Man machine - and in particulair the displays, Ecam messages etc. for NON Airbus pilots is excusable.....but NOT TO Airbus pilots.

3.2 Causes of the Accident:
------




Thus, the accident resulted from the following succession of events:
  • Temporary inconsistency between the airspeed measurements, likely following the obstruction of the Pitot probes by ice crystals that, in particular, caused the autopilot disconnection and the reconfiguration to alternate law;
  • Inappropriate control inputs that destabilized the flight path;
  • The lack of any link by the crew between the loss of indicated speeds called out and the appropriate procedure;
  • The late identification by the PNF of the deviation from the flight path and the insufficient correction applied by the PF;
  • The crew not identifying the approach to stall, their lack of immediate response and the exit from the flight envelope;
  • The crew’s failure to diagnose the stall situation and consequently a lack of inputs that would have made it possible to recover from it.
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Old 6th Jul 2012, 08:35
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question

I`m not apilot by far.But I`ve read a few a.i. reports, so i think i know a bit more than the common man on the street.

sp pls somebod answer my question.Would`nt a simple spirit level (water gauge) in the cp have heled ?
There a so many technical revolutions today ,flying to the stars.why is it not possible to have a display in the cp showing the attitude of the ac from outside (head up-tail down) with a big blinking red arrow under the fuselage pointing downward,combined with an alarm and a voice,saying "correct your attitude" which can`t be cancelled until this has been done ?
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Old 6th Jul 2012, 08:52
  #74 (permalink)  
 
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Something in the CVR transcript I have not seen til now... Very late in the text.

2:13:53.0. Page 31 CVR transcript (English)

Captain: "So wait...AP off". (sound of selector button....)

Que?
The AP is off from the beginning of the event
I suppose the captain moved the AP selector to OFF (useless command IMHO)
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Old 6th Jul 2012, 08:56
  #75 (permalink)  
 
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Quote:
Is 60 kt really too low cut-out for widebody?

Originally Posted by ECAM_Actions View Post
It would seem not slow enough. :ugh
As discussed at length before it is 60kt 'apparent airspeed' derived from pitot tubes which will all be significantly under-reading at high angle of attack. I'm sure someone can post a calculated trace of actual speed through the air, taking into account vertical and ground speed and estimated wind.

Why 60kt? To read a 10:1 turndown in airspeed in range 30-300 needs a 100:1 turndown on the pressure sensor - so just double the lower value to make sure we can measure it?
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Old 6th Jul 2012, 09:10
  #76 (permalink)  
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Originally Posted by ECAM Actions
Besides - the FD bars on the AF jet were commanding a CLIMB,
- I very much hope EA is not a pilot but if he/she is that this view is not common across the industry. We have seen this 'concept' a few times on the previous threads and it does demonstrate a complete lack of understanding as to how aircraft fly.

Last edited by BOAC; 6th Jul 2012 at 09:12.
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Old 6th Jul 2012, 10:02
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Originally Posted by page93
The turbulence was modelled by introducing gusts so that the simulated parameters were copied from the parameters recorded.
That information was missing in Interim #3 and explains the AoA variations without pitch variations in the simulation prior to A/P disconnect. It remains odd that the normal acceleration trace does not reflect the AoA variations.
Originally Posted by page 188
In the specific case of alternate 2B law, some coefficients used in the longitudinal flight control law become speed-independent and are set for the maximum speed for the aeroplane configuration (330 kt in clean configuration).
This may explain the difficulties I encountered in trying to correlate the side stick commands to the airplane response.

Originally Posted by sensor validation
I'm sure someone can post a calculated trace of actual speed through the air, taking into account vertical and ground speed and estimated wind.
Apologies if it has been posted earlier. Strangely the report never mentions that the IAS becomes increasingly erroneous after the AoA exceeds 25 degrees.


Last edited by HazelNuts39; 6th Jul 2012 at 12:08.
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Old 6th Jul 2012, 10:29
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When was this lecture?


It certainly pre-dates AF447 accident but is creepily prescient.
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Old 6th Jul 2012, 11:21
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Exactly. It's from 1997. Had the same stuff in 1988 in the RAF. Gave the same stuff in 1992.
This is why airlines should run their own training schools, ab initio, not rely on self-financed pilots getting trained by anyone they think will pass them at the most affordable price.
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Old 6th Jul 2012, 12:40
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Question to all those who fly for a living or have done so:

Would you have, as Captain, taken a rest break right before traversing the ITCZ?

A question was raised in the final report about the timing of the Captain's break but was sort of brushed aside. Perhaps there would have been a different outcome had the Captain stayed awhile longer in the cockpit but that's easy enough to state in hindsight.
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