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Sully's Flare on the Hudson: Airbus Phugoid Feedback

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Sully's Flare on the Hudson: Airbus Phugoid Feedback

Old 27th May 2017, 00:12
  #121 (permalink)  
 
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Originally Posted by Whoo
The old suggests double engine flameout land/ditch in Conf1. Abbreviated recommends Conf2.
I don't see the logic behind the difference neither, but I would think Airbus soon will also modify the ALL ENG FLAMEOUT to CONF2 to match the new EMERGENCY LANDING ALL ENG FAILURE ...

Originally Posted by vilas
When Sully was pulling full back stick to get flare how can he be out of alpha prot?
You are correct, he was still under alpha protection mode below 50ft, despite the fact he was not even in the alpha protection range. So margin there was to improve touchdown.

Originally Posted by tubby linton
I do wonder what you are trying to prove with your discussion of the protections
I won't tell for QA, but my point is merely to counteract unsubstantiated comments such as :
  • Sully would have stalled if not protected
  • Sully started the APU to remain protected
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Old 27th May 2017, 00:39
  #122 (permalink)  
 
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The A vs B discussion is usually a robust sign that a thread is pretty dead. Anyway I find the airspeed discussion more interesting than phugoid damping...but I for the record I felt compelled to add that I believe their airspeed, under "just culture", was an honest mistake. (one never knows who else might read these threads). Nothing was normal that day. Pitch wasn't "normal". ECAM (a lot, despite some inhibited warnings). TCAS. Windshear. Priority Left. GPWS and EGPWS. There's too much noise. QRH is either too long and/or irrelevant (like evacuation - select parking brake on).

The flight envelope protection debate...Sullenberger flew the aircraft and everybody walked away. I briefly wondered if he was actually aware of what mode/law it was in (was he thinking "what's it doing now" when he pulled the stick back full?), but for myself I came to the conclusion it did not matter there in that particular case.

Sullenberger and Skiles were prepared for the unexpected. They managed the unexpected. For me that's a key takeaway.
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Old 27th May 2017, 03:18
  #123 (permalink)  
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The A vs B discussion is usually a robust sign that a thread is pretty dead.

I wouldn't have thought that there has been other than sideline A vs B in the thread ? It is difficult for those of us who have only flown the one, to appreciate the subtleties of the other .. hence some comparison in discussion probably isn't a bad thing ?

The thread is going around in circles a little but, overall, I think it has value yet to be explored.

I believe their airspeed, under "just culture", was an honest mistake.

It is evident that no-one is suggesting otherwise .. indeed, I have no doubt that all here are quite fervent in their .. "rather them than me" quiet thoughts.

Sullenberger and Skiles were prepared for the unexpected. They managed the unexpected. For me that's a key takeaway.

Indeed.
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Old 27th May 2017, 07:43
  #124 (permalink)  
 
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I won't tell for QA, but my point is merely to counteract unsubstantiated comments such as
I clarified that it was NTSB which thinks switching on APU was smart thing because the aircraft remained in normal law, I produced the clip to substantiate it. I didn't say that was the only purpose. Also I explained that in this particular accident APU didn't matter. As against this you make statements like
Truth is that Sully would have most probably obtained a better touchdown with direct law.
Only your opinion without any substantiation. It is possible he probably would have stalled.
Below 150ft it was.
And additionally passing 50ft it was not anymore.
Again opinion without any evidence, even erroneous.
The truth is it is not possible to enter into alpha prot below 200ft if correct speed is maintained.
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Old 27th May 2017, 13:32
  #125 (permalink)  
 
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Originally Posted by tubby linton View Post
I do wonder what you are trying to prove with your discussion of the protections, or is it data gathering for a law suit?
I believe he wants Airbus to be "admonished" more sternly. I'm wondering why he can't just write a strongly-worded letter to them. I'm sure that will instill the fear of Krishna into them lickety-split.
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Old 28th May 2017, 05:05
  #126 (permalink)  
 
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Originally Posted by vilas
Again opinion without any evidence, even erroneous.
Below 50ft a-prot was at 15,5 deg and a-max 17,5
The airplane was 1,5deg short of a-prot and 3,5 from a-max
Are you pretending the data are erroneous ?

If aircraft would have been in alternate law it would have stalled.
It is possible he probably would have stalled.
Finally you are getting more cautious.
Would you meet Sully and Skyles :
"Congratulations, but how lucky were you not to stall ... thanks to the a-protection"
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Old 30th May 2017, 23:16
  #127 (permalink)  
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Originally Posted by tubby linton View Post
Quagmire, Halifax was due to pilots forgetting to fly the aircraft, rather than just watching the automation. It had nothing to do with the aircraft protections..If they did pull up it would have been load factor protection to +2g as the flaps were out, and this protection is using the aircraft certified limits as a target. I do wonder what you are trying to prove with your discussion of the protections, or is it data gathering for a law suit?
Its obvious the Halifax accident started from using flight path angle hold and drifting down. That part is clear, in only the first part of the scenario.
Understand when the pilots finally pulled up, it would be helpful to know if they were able to use all the alpha possible, up to stall, close to the ground where they tried to pull up. .... Why assume it took over 2g's to recover? Any evidence of that, like FDR plots? Or just a guess? We need FDR plots.

When I started this thread, I was exploring what happened between the Aircraft Performance Study statements for the Sully incident and the NTSB Accident report, and later found some other BEA involvment and earlier NTSB statements. Then some on here reminded me there have been other similar alpha-protect accidents in the past. Then the FAA statements were found. I'm not involved with lawyers or courts, and just want the NTSB and FAA to stand up for their own statements. The way the world works, governmental authorities like those are the way to get real change.
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