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Southern Air 777 stall and recovery after takeoff, Nov 15th

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Southern Air 777 stall and recovery after takeoff, Nov 15th

Old 24th Nov 2020, 15:56
  #81 (permalink)  
 
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Don’t know which departure they were flying. Some airlines require quick engagement of the autopilot on RNAV departures.
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Old 25th Nov 2020, 04:02
  #82 (permalink)  
 
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Originally Posted by VThokie2 View Post
Again highly unlikely they will ever have to meet with a CP for a “carpet dance” (as we say here) over this.
That's right. The armchair puddles here relish the thought of some crew getting clobbered over tea and stale British cookies, but that hasn't been the norm in a modern company (which this is), for many years. Back to flight simming, guys.
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Old 25th Nov 2020, 08:03
  #83 (permalink)  
 
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Uplinker. A bit like you, I flew the 787 for a short while. Most of the time it was fine but I did see a few times drops of 20kts during capture.

It felt like the system was overly compensating for the impending level off with huge movements of the levers. As a pure guess, maybe Boeing have a simple power reduction logic that only looks at altitude to go vs current ROC, whereas they should be factoring in some combination of CG, winds and temperature delta.
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Old 25th Nov 2020, 08:29
  #84 (permalink)  
 
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777 is FBW, right?

Does it not have high alpha or stall protection?
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Old 25th Nov 2020, 08:38
  #85 (permalink)  
 
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lucille: same question was asked by ManaAdaSystem and answered on here yesterday:

"The 777 design utilizes envelope protection in all of its functionality rather than envelope limiting.
Envelope protection deters pilot inputs from exceeding certain predefined limits but does not prohibit it"


Gregg Bartley, Boeing

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Old 25th Nov 2020, 12:04
  #86 (permalink)  
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I would imagine the crew would report this incident themselves. Better to own up than await a phone call from the analysts who conduct Flight Data Monitoring. Perhaps after this they might be rostered a training sim as part of finalising and debriefing the safety report. As others have said all this conducted hopefully in a non punitive way assuming it’s an “honest” mistake and not a deliberate deviation from SOP. Not saying this crew did that, benefit of the doubt etc. I suspect we won’t hear what happened.
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Old 25th Nov 2020, 14:29
  #87 (permalink)  
 
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Any one can make a mistake. Provided it is reported or, if picked up by the FOQA system, discussed honestly with the designated representatives, there is nothing to fear and every one will learn. Depending on the nature of the mistake, some extra sim training may be appropriate for the individuals concerned or, if there are wider implications, new information disseminated, included in training routines, and/or manuals and procedures may be changed for everyone's benefit. But as Check Airman has intimated, lying about it cannot be tolerated.
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Old 25th Nov 2020, 15:45
  #88 (permalink)  
 
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Bergerie1, you write that as if it's a global policy. It should be of course, but it's not. Unfortunately there are still too many countries who don't grasp that concept and continue to go down the blame and punish route.
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Old 25th Nov 2020, 15:54
  #89 (permalink)  
 
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oldchina

Thanks. Yes, I missed seeing it the first time around.

What exactly does “deter” mean in this context? Surely not stick shaker and pusher in this day and age.?

My very limited understanding of the MAX was that it was envelope limiting w.r.t. AoA. I had (incorrectly) presumed that same philosophy may have been borrowed from the 777.
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Old 25th Nov 2020, 16:14
  #90 (permalink)  
 
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Originally Posted by lucille View Post
What exactly does “deter” mean in this context? Surely not stick shaker and pusher in this day and age.?
The T7 does have a Stick shaker as the final line of defence.

I don't have the FCOM in front of me but for example the stab trim cuts at as you approach the stall, preventing you trimming "into the stall", and providing a tactile cue that something is amiss...

Somebody with access to the FCOM will no doubt be able to provide a full list the other items designed to hint or "deter" .
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Old 25th Nov 2020, 16:21
  #91 (permalink)  
 
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Absolutely! We are talking about the minority of countries that actually have a 'no blame' culture! The vast majority of the world, and the big ME3 would sack you immediately, and shove a pineapple up your posterior on the way out, just to prove a point!

Good for all of you above posters, but this isn't how incidents like this are treated in 75% of the world.
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Old 25th Nov 2020, 17:01
  #92 (permalink)  
 
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Pistonprop, I agree entrely, and I write it is an ex-CP
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Old 25th Nov 2020, 18:57
  #93 (permalink)  
 
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Originally Posted by Pistonprop View Post
Bergerie1, you write that as if it's a global policy. It should be of course, but it's not. Unfortunately there are still too many countries who don't grasp that concept and continue to go down the blame and punish route.
We understand that and when our brethren on here proclaim that this crew will most certainly be going in for Tea and Biscuits with the CP, those of us in this safety culture here in the US are commenting that they most likely will not (unless lying is involved). We are simply educating how this incident will be handled over here. Spending several years as an expat I was disgusted with what people convinced themselves of was a “just safety culture” with some level of punishment being an ever present integral part of said culture.
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Old 25th Nov 2020, 19:33
  #94 (permalink)  
 
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This is the full Boeing bible on the 777 FBW controls, that I was copying from. It includes::

"For example, the 777 bank angle protection feature will significantly increase the wheel force a pilot encounters when attempting to roll the airplane past a predefined bank angle. This acts as a prompt to the pilot that the airplane is approaching the bank angle limit. However, if deemed necessary, the pilot may override this protection by exerting a greater force on the wheel than is being exerted by the backdrive actuator. The intent is to inform the pilot that the command being given would put the airplane outside of its normal operating envelope, but the ability to do so is not precluded. This concept is central to the design philosophy of the 777 Primary Flight Control System."

https://www.davi.ws/avionics/TheAvio...ook_Cap_11.pdf


Last edited by oldchina; 25th Nov 2020 at 19:48.
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Old 25th Nov 2020, 22:47
  #95 (permalink)  
 
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FWIW f you dive into the FCOM (I'm no longer current on type and so am looking at the old paper version) there's a whole section on Stall protection which covers autothrottle response and it's limitations at low altitude, plus EICAS warnings such as "Airspeed Low"..
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Old 26th Nov 2020, 00:03
  #96 (permalink)  
 
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I still don't see the answer to this. Did the power reduce, or were the flaps retracted prematurely? The later seems more likely as other protections are in place to cause a stall recovery. The power reduction is quite noticable and would get the crews attention rather quickly whereas a premature flap retraction would be more subtle IMO. Having experienced the latter in a MD11 once upon a time it remains etched in my memory. Either way it appears they handled it well.
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Old 26th Nov 2020, 02:24
  #97 (permalink)  
 
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From 1400’ onwards, the airspeed did not decrease. The PM reconfirmed the departure frequency with tower. IMHO, it is likely that PM was focusing on the radio frequency and selected a wrong flap retraction setting. Looking at the speed, possibly he went from flap 5 to up combined with the PF not-so-positive’ acceleration, possibly with large thrust reduction at altitude capture.
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Old 26th Nov 2020, 02:41
  #98 (permalink)  
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Just happen to have seen this almost generic reminder of the way big engines shield a substantial chunk of wing. It really is 'A little bit more can give a while lot less.'

https://www.quora.com/Whats-the-use-...ting-downwards
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Old 26th Nov 2020, 07:34
  #99 (permalink)  
 
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Originally Posted by flightleader View Post
From 1400’ onwards, the airspeed did not decrease.
Out of interest, where are you seeing information on airspeed?

Last edited by DaveReidUK; 26th Nov 2020 at 12:09. Reason: typo
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Old 26th Nov 2020, 10:10
  #100 (permalink)  
 
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ATC radar records above
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