Air France 447

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There is nothing to be learned from those who dismiss these accidents simply citing: the "probability that another crew would do the same given the same circumstances."

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But, from the School-of-Thought Camp that says : 'Let's analyze this accident and see if we can determine what the pilots did wrong, or could have done better....'
.......This is the typical formula for aircraft accidents, a chain of events that lead to tragedy. In this case it was natural phenomenon, design flaws, and human error all rolled up into one.........


Human Factors in Air France Flight 447

Some of the facts brought out in the third interim official report were -
  • “The Captain’s departure from the deck occurred without clear operational instructions.
  • There was no explicit task-sharing between the two copilots.
  • The AP (autopilot) disconnected while the airplane was flying at upper limit of a slightly turbulent cloud layer.
  • There was an inconsistency between the measured speeds, likely as a result of the obstruction of the Pitot probes in an ice crystal environment.
  • At the time of the autopilot disconnection, the Captain was resting.
  • Even though they identified and announced the loss of the speed indications, neither of the two copilots called the procedure “Unreliable IAS”.
  • The copilots had received no high altitude training for the “Unreliable IAS” procedure and manual aircraft handling.
  • No standard callouts regarding the differences in pitch attitude and vertical speed were made.
  • There is no CRM training for a crew made up of two copilots in a situation with a relief Captain.
  • The approach to stall was characterised by the triggering of the warning, then the appearance of buffet.
  • A short time after the triggering of the stall warning, the PF applied TO/GA thrust and made a nose-up input.
  • In less than one minute after the disconnection of the autopilot, the airplane was outside its flight envelope following the manual inputs that were mainly nose-up.
  • Until the airplane was outside its flight envelope, the airplane’s longitudinal movements were consistent with the position of the flight control surfaces.
  • Neither of the pilots made any reference to the stall warning.
  • Neither of the pilots formally identified the stall situation.
  • The Captain came back into the cockpit about 1 min 30 after the autopilot disconnection.
  • By design, when the speed measurements were lower than 60 kts, the 3 angle of attack values became invalid.
  • Each time the stall warning was triggered, the angle of attack exceeded its theoretical trigger value.
  • The stall warning was triggered continuously for 54 seconds.
  • The airplane’s angle of attack was not directly displayed to the pilots.
  • Throughout the flight, the movements of the elevator and the THS were consistent with the pilot’s inputs.
  • The engines were working and always responded to the crew’s inputs.
  • No announcement was made to the passengers.”
Although the investigations are still continuing, an earlier interim BEA report had already suggested that the crash occurred due to aerodynamic stall at high altitude. The pitot tubes were found have provided inconsistent readings minutes prior to the accident [3]. Going further, the third interim report suggested certain training related issues viz., that the co-pilots were not “trained to fly the aircraft at high altitude in manual mode with unreliable airspeed indication”[2].

BEA has recommended mandatory training on flying with the autopilot disabled, as well as recovery from high-altitude stall [2].

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Source: #1 Aviation Medicine
http://www.avmed.in/2011/08/loss-of-control-human-factors-in-air-france-flight-477/

#2: Official Report: French Bureau of Enquiry and Analysis for Civil Aviation Safety
http://www.bea.aero/fr/enquetes/vol.af.447/note29juillet2011.en.pdf
http://www.bea.aero/fr/enquetes/vol.af.447/point.enquete.af447.27mai2011.en.pdf
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Source? .....A buddy is an A380 test pilot and will flatly deny that.

I saw this in a Quantas news release too.
And of course, anyone that works for Airbus will deny it. That's not a shock to anyone here. Would you expect him to admit that that put millions of dollars and hundreds of people at risk so they could make a profit? Oh, come on!!
 
I saw this in a Quantas news release too.
And of course, anyone that works for Airbus will deny it. That's not a shock to anyone here. Would you expect him to admit that that put millions of dollars and hundreds of people at risk so they could make a profit? Oh, come on!!

Every time, and I mean EVERY time we strap on a jet we are risking peoples lives. We work in a high risk industry. Just choosing to fly creates risk. Choosing to fly if there is any weather creates MORE risk. Choosing to fly with ANY item of deferred maintenance adds still more. We are in an industry where we balance that risk against the choice of not operating at all. Where do we make that cut.

I can tell you that PILOTS are more likely to misjudge that than engineers, on balance.
 
Source? A buddy is an A380 test pilot and will flatly deny that.

From reading the articles at the time, it was a known issue, a fix had already been developed for it, and new engines leaving the line already had the fix, Rolls Royce considered it to be a minor problem that could be addressed during overhaul. I really don't think there's any conspiracy, just someone's judgement call that turned out to be wrong.
 
I am surprised the A380 is still flying especially with wiring issues which I read were first address in 2009 and are still not sorted out to this day. I have been discussing this accident and the news stories refer to fuel transfer problems – left, right and fore and aft due to the wiring being blown out. Pilots were particularly concerned that the stricken plane would get tail heavy and stall as they could not pump the fuel out of the vertical tail fin forward to the wing tanks. So how was this resolved in this instance? Also is there a manual valve that can be opened to dump the from the tail tank?
 
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