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AF447 wreckage found

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Old 6th Aug 2011, 01:46
  #2661 (permalink)  
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My personal "artifical horizon" always works:
Well in this scenario your artificial horizon may not have worked quite as you have expected.

With a 15 degree nose up attitude with a very high rate of decent, but no change in accel/decel you would have felt your * erse against seatback = climb. Unfortunately it was decent.

There you go.
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Old 6th Aug 2011, 01:57
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My airline never said pull up to 7,000 FPM climb if I lose my airspeed in the clouds. Something like hold cruise pitch and power.

Of course we already knew this before we got hired having flown several dozen types of aircraft single pilot in most cases and quite a few jets with lots of time.

The new way of training airline pilots in automatic airplanes makes them systems operaters, not real hands on pilots. I think we will see more of these accidents as the old guys retire and the systems operaters take over the cockpit.

Last edited by bubbers44; 6th Aug 2011 at 02:13. Reason: addition
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Old 6th Aug 2011, 03:05
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"I think we will see more of these accidents as the old guys retire and the systems operaters take over the cockpit."
No doubt "more of these", but also - less of those - . . . for now . . that's progress . . (and I don't like it!).
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Old 6th Aug 2011, 03:27
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Originally Posted by Graybeard
Birgenair was different, because the lower ranked FO knew what was happening

..........DW: As did the PNF in this case, judging by the CVR.

GB: The FO could have overpowered Capt. by pushing harder on the yoke. Could he have done that with a joystick?

DW: If he'd called "I have control" and pressed the priority button, of course he could have. The issue for the Birgenair F/O, as it was for the AF447 PNF was that he wasn't assured enough of his assessment of the situation to take positive control and hold it.

GB: As for your argument that the 777 backdrive can fail: it's built to the same safety standards as the Cat IIIc autoland, i.e., 10 -(7?) probability of undetected failure.

DW: As are the Airbus systems, so why trust one system and not the other?
It's you who previously threw out the probability of a 777 backdrive failure rendering it no better than a joystick.

The 777 backdrive provides continuous feedback to the PNF of the commands by the PF and AP. And it is in the peripheral vision at all times, even while the PNF is attending the ECAM. The PNF doesn't have to focus on the EFIS to interpret the commands.

And you're wrong to equate a high ranking Capt on Birgenair to the AF 447 PNF copilot. The 447 PNF seemed to be less aware of PF actions, because there was no yoke!

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Old 6th Aug 2011, 03:46
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@DW

but to argue that the stall warning significantly and repeatedly stopped the PF from doing the right thing (nose down) because the warnings were triggered *as a result* of his nose-down input is untrue.
I think we will never know. None of us can get inside the PF's head to know exactly what he was thinking. It's possible that the stall warning had zero influence on his behavior. OTOH, it's possible that it did. I agree with you that the stall warning did not "significantly and repeatedly stop" the PF from doing the right thing. OTOH, a more robust design might have been just the little nudge he needed in the right direction. On that point we will never know.
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Old 6th Aug 2011, 04:17
  #2666 (permalink)  
 
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Cool

Hi,

I think we will see more of these accidents as the old guys retire and the systems operaters take over the cockpit.
That's possible
What we know for sure .. is that possible that a high technology plane with the latest flight security systems (redundancy .. protections and limitations ... or like some tell ... fool proof) can go from a eventless flight at 35000 feet .. to the ground in 4 minutes .. just because a indication speed lost forced the pilots ( from a major European airline) to manually fly the plane (even with some aids still working)
That's a "premiere" .. and hopefully not the first of a serie ......
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Old 6th Aug 2011, 05:30
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Ultimately, it's all irrelevant.

Airbus,and I suspect Boeing, never expected a pilot to put their plane through this.

The long chain, and Swiss chess, started when this pilot was accepted for flight training.
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Old 6th Aug 2011, 05:56
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@jcjeant

Medical license.. Try to get a license in NyC. They stop short of asking for your kindergarten reports... Especially if you are FMG you need to provide everything and thy contact your Med School to see if it is legit. But I agree, it can happen in our field too...

Last edited by grimmrad; 6th Aug 2011 at 10:55.
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Old 6th Aug 2011, 06:09
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Cool

The long chain, and Swiss chess, started when this pilot was accepted for flight training.
And even more drastically .. it begins with his birth ...
The problem is to detect incapacities (if any) by testing .. or more hypothetically .. at birth
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Old 6th Aug 2011, 08:34
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t least ....
At the speed with which they came down .. they would certainly have some effect at the eardrums due to pressure difference ... (hurt feeling)
Even at reasonable rate of descent you feel this (even if cabin pressurised)
In a media report / briefing there was some talk of the passengers knowing/not knowing of the decent over 4 minutes.. I was unable to find any reference to this comment in print anywhere. Could someone point me in that direction. Additional query would be if the sensation of rocking and falling would feel like bad turbulence or would there have been a sensation of weightlessness / Incapacitation etc.

Not a lawyer!!!
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Old 6th Aug 2011, 14:07
  #2671 (permalink)  
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Quoting Neptunus Rex:-

Not quite. Manual pitch trim should have been available in both cases.
I don't think so, Neptunus. Don't forget, 'autotrim' was still operating; and I don't think Airbus pilots have the option of turning it off? So if they'd wound the trimwheel forward to reduce the huge (13-degree) 'up' angle the systems appear to have imposed, the autotrim would presumably just have wound it back to 'Square Thirteen' again?
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Old 6th Aug 2011, 14:57
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Quoting RWA:

...if they'd wound the trimwheel forward to reduce the huge (13-degree) 'up' angle the systems appear to have imposed, the autotrim would presumably just have wound it back to 'Square Thirteen' again
The systems only imposed the 13 degree up angle because the pilot asked for it by backwards pressure on the SS that increased the pitch angle to the point where the aircraft stalled - the system was doing exactly what the pilot requested. Even then, if he'd moved the SS forwards again to try to reduce the pitch angle (and consequently the AOA), as you'd expect any pilot to do when in a stall, the system would've moved the THS accordingly.
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Old 6th Aug 2011, 15:00
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Cool

I don't think so, Neptunus. Don't forget, 'autotrim' was still operating; and I don't think Airbus pilots have the option of turning it off? So if they'd wound the trimwheel forward to reduce the huge (13-degree) 'up' angle the systems appear to have imposed, the autotrim would presumably just have wound it back to 'Square Thirteen' again?
I don't think so
If pilot had moved the trim .. he take authority over the auto trim and the trim will stay where the pilot put it ... and the trim will not return in primitive position
AFAIK

Remember the Westland Lysander ??
This old plane had already "auto flaps" !
They deployed or retracted regarding of the aircraft speed ...
They had a big effect on the flight attitude of the plane (don't forget to trim !!)
If the pilot dont know that .. it was the crash as result .. at landing or take off
If you don't know the plane you fly .. the result can be a catastrophe .. Lysander or A330 .. same results

Last edited by jcjeant; 6th Aug 2011 at 16:29.
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Old 6th Aug 2011, 15:03
  #2674 (permalink)  
 
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Quote from grimmrad:

Regarding the question about a license... does that mean you can be pilot in a major carrier WITHOUT the license??
No - all of the pilots had licences - the list of qualifications each pilot held is in the BEA report. The captain was asking whether the licence he held "qualified [him] to act as relief" (quote from from the BEA report).
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Old 6th Aug 2011, 16:18
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Cool

No - all of the pilots had licences - the list of qualifications each pilot held is in the BEA report. The captain was asking whether the licence he held "qualified [him] to act as relief" (quote from from the BEA report).
Indeed .. and it's a odd question of the captain when replaced in the context
(this copilot made also with same captain the flight Paris - Rio ... and captain don't know the qualifications of his crew ... show at least the no professionalism of the guy ... or bad Air France rules )
Go figure the logic .....
By the way .. it's not a part of the CVR transcript ... it's reported by BEA
Waiting for the full CVR transcript ....
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Old 6th Aug 2011, 16:28
  #2676 (permalink)  
 
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Still unanswered

OK, I've gone and read details in the Tech Log thread, but there still seem to be some questions the BEA hasn't answered, or hasn't tried to answer. (Or if so, I've missed them.)

Why the initial climb?

As for the pilots not recognizing they were in a stall, I think that is because they knew some instruments were not working --- but did not know which were working --- so they were totally confused about what was true and what wasn't. I know someone said earlier pilots were supposed to know which instruments were fed by what, but that's not the same as knowing in a real life situation which instruments can actually be relied upon. I wonder how many pilots would really know. I don't think any amount of training would solve this problem. Obviously technical solutions are limited. Put an indicator next to the instrument indicating its value is valid or not, then how do you know if that indicator is working correctly!
But I certainly don't see this as pilot error.

From the transcript, the conversation suggests they clearly didn't know the seriousness of their situation.

Why WAS the THS stuck up? Down inputs were recorded or mentioned. The BEA emphasizes the plane was fully functional and responsive, so why was the THS stuck up and remained stuck up?
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Old 6th Aug 2011, 16:32
  #2677 (permalink)  
 
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It wasn't stuck up.
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Old 6th Aug 2011, 16:40
  #2678 (permalink)  
 
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jcjeant said:
If pilot had moved the trim .. he take authority over the auto trim and the trim will stay where the pilot put it]
Well said master!

Will edit once more... Reminder: "Speed = Life"... On doubt... Always Speed! Why?
Coz the wings fly... (And speed is AoA, no engines involved).

Last edited by TioPablo; 6th Aug 2011 at 16:56.
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Old 6th Aug 2011, 16:51
  #2679 (permalink)  
 
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Cool

Why WAS the THS stuck up? Down inputs were recorded or mentioned. The BEA emphasizes the plane was fully functional and responsive, so why was the THS stuck up and remained stuck up?
Check Technical Log forum
It's explained (many time by takata and some others) with drawings of the system logic and also graphs extracted from BEA report N*3
Make your searches .. be informed.
BTW the THS is not stuck (blocked)
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Old 6th Aug 2011, 17:16
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THS

OK, I stand corrected that the THS wasn't "stuck up". I recall a number of posts trying to figure out why it was up, and whether it was stuck, broken, etc. But it seems to have been up (for whatever reason) and stayed up. Has the BEA explained why?
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