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Emirates B777 gear collapse @ DXB?

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Emirates B777 gear collapse @ DXB?

Old 18th Sep 2016, 07:05
  #1621 (permalink)  
 
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Vilas, thanks for your reply. Don't get me wrong: I'm not manual-flight mad (I could be the biggest nerd in my outfit, but I handfly when I can because it improves my ability and comfort in getting rid of the automation if I need to). In my view, the balance at the moment is 95% automation, 5% manual. The 95%ers are simply unable to do/revert to the 5%. Aeroplanes are crashing needlessly because of it. The imbalance needs to be addressed.

All those Airbus rules presuppose one thing: that the crew are competent and happy and willing to decrease the automation level, instinctively if that's what it takes, as needed. It is painfully obvious that increasingly, crews are not competent and happy and willing to decrease the automation level.
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Old 18th Sep 2016, 07:36
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If we’re talking about learnt behaviours, removing your hand from the TLs at V1 and joining the other one on the yoke (for the eminently sensible reason of trying to avoid a post-V1 reject) is something that could happen during an unintentional touch-and-go. The triggers are there: on the runway and close to or at rotation but the action is inappropriate for the circumstances. If the startle factor is strong, falling back to something that’s done on every flight is more likely than executing a sequence that, at best, has been practiced only a few times over a career in a different environment.

Slightly tangentially, I was observing the other day that ANR headsets have become effective to the point that with some aeroplane/headset combinations you can’t hear the engines at all, so that information channel has been muted or lost. I’ve taken to turning off the ANR function (the 777 has a quiet flight deck to begin with) on takeoff and landing as it almost feels like you’ve gone deaf...
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Old 18th Sep 2016, 07:40
  #1623 (permalink)  
 
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I think to start with this is possible.
Take off emergency briefing:
" If any abnormality before V1 I will call Stop or Go, if the call is go..........."
Approach briefing:
" In case we go around at minima I call GA and trigger the GO levers and ........... In case we GA after touch down I will manually push throttles to TOGA position and you ensure TOGA thrust .........."
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Old 18th Sep 2016, 08:35
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if the normal action is to press & forget TOGA for a GA, but in this high stress scenario it is not the correct action, is the system design to the optimum?
No
The skills are acquired over time.
And they fade over time.
How long had it been since he was manually manipulating the thrust? The neural pathways involved in the action were how rusty?
It is painfully obvious that increasingly, crews are not competent and happy and willing to decrease the automation level
I agree. Why is that? Because when they do, they have to devote significant amounts of mental resource to the simple act of flying and they worry they will do a rough job of it or worse, miss a big picture element that is important. The only solution is to do more flying but every month that passes sees them losing more confidence and becoming less likely to hand fly.
It is just the 'chimp' (in ALL of us!!) jumping to the wrong choice of action. That's all.
I agree 100% with 4468 above.
So how do we remedy this? Is it by asking the chimp ( in all of us) to recognise that they are mentally overloaded, stop frantically trying to process the barrage of information presented to him, remember back to the briefing he received at four am five months ago, compare that to the knowledge stored in his long term memory regarding auto throttle design, compare that to the current situation unfolding, and then select the correct choice of action. Or, is it to ensure that the ' go to ' course of action is one that will never leave you at 85 ft with no thrust?
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Old 18th Sep 2016, 09:17
  #1625 (permalink)  
 
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Regarding the debate about regular manual manipulation of the a/c being a cure for avoiding these traps and allowing for confident control in those occasions when it is required: these accidents of serviceable a/c seem to happen on large intercontinental operating a/c. 10-12hr sectors = 6-10 sectors per month. 4-5 landings for each pilot minus, perhaps, a mandatory or necessary autoland; and then also having to share perhaps with a 3rd pilot. Thus maintaining manual control skills will not be so easy. Equally, at the end of a 14hr night, it might not be the best option. So easy to say, but difficult to achieve.
Now, there are airlines that operate these large a/c on short-haul high density routes. They do have the opportunity. Do they? They could also have huge amounts of R&D data to feed back to the manufacturer. Do they? Has this Gotcha, and others, happened before? The SFX incident had, but that operator was not so aware of it. Why not?
What I find disappointing is that many short-haul 50sector/month pilots are discouraged by company culture from manual flying. How long before the technology of large a/c filters down to small/medium type and these problems and scenarios migrate into that world? If it does it will be a really sad day for the industry that will not have learnt from precedents. We shall see.
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Old 18th Sep 2016, 09:24
  #1626 (permalink)  
 
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Equally, at the end of a 14hr night, it might not be the best option. So easy to say, but difficult to achieve.
I agree. I think the answer is a long way off ( maybe a decade) and will involve more regular sim visits. Once every eight weeks into the sim for a couple of hours of manual flying would be great but will only come when Jo public starts jumping up and down.
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Old 18th Sep 2016, 10:23
  #1627 (permalink)  
 
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Guys (girls?)

We're in danger of solving the wrong problem here!

What makes you think he wasn't able to hand fly the aeroplane? His middle names could be Chuck and Yeager, but even if he hand flew every single approach, how many times would he have had the opportunity to 'fly' a go-around after landing????

I bet there aren't many of us here that have done one for real. Hopefully we never have the requirement to. Fly a thousand manual approaches and it won't help you in this scenario one bit!

Knowledge and training (that means in the sim) is the only answer. Along with pre-briefing at moderately frequent intervals, such as when you operate to short runways, to at least keep the procedure fresh in your mind for when the requirement comes out of the blue, like here!

This pilot shouldn't have pushed the TOGA buttons on the ground AT ALL! If that's what happened, the chimp had instantly selected the WRONG motor program! He shouldn't have 'monitored' the thrust levers at all, he had to firewall them!

It's nothing to do with manual flying skills per se! It's about practicing THIS PARTICULAR MANOUVRE!

Solve other problems by all means. But they aren't what caused this accident!

The chimp is alive and well in every single one of us!! When we lived in caves he kept us alive. In a modern jet we need to watch him like a hawk!

Last edited by 4468; 18th Sep 2016 at 10:49.
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Old 18th Sep 2016, 10:50
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Aspects of human behaviour and training discussed in recent posts are like comparing a stone and a bird.
You can throw a stone with some confidence of where it will land, but when throwing a bird there is no control over the destination (a bird has human-like behaviour); where even with training and practice the best can deviate from the intention.
It is possible to make the bird more like a stone, clip its wings, bind it up, (procedures and practices), but then you loose the bird's ability to avoid hazards, especially those previously unseen en-route.
However, a bird might be encouraged to reach the desired destination by suitable placement of birdseed, change or add something to facilitate the desired behaviour.

In this accident an objective would be to apply and check GA thrust. Verification might better be achieved by looking at the engine instruments opposed to relying on feedback from moving thrust levers.
An alternative is to move the thrust levers as part of the GA switch, this also guides the eye to the thrust instruments; feed-forward guidance vice feedback.

Rigorous training and SOPs constrain pilots and will not guarantee appropriate behaviour in all situations, but with thought about the complexity of the task, time constraints, and workload, pilots can be helped to achieve the desired objective. Those who should consider these changes, regulator-manufacturer-operator, must have sufficient understanding of systems and integration - interaction, and the operational environment (professional culture, policies, procedures) in order to form an adequate judgement; they have to resolve complexity, redefine the task, simplify the manoeuvre, and in using their time wisely might benefit safety, perhaps reducing training costs as well.

The industry has to avoid being like a turkey, being cooped up in the office, single focus - overfed, and with little foresight, particularly about the days of the month - beware of, and learn from surprises.

Bird - Stone analogy from "The logic of failure" by D Dorner, ( English version) 1996, 'Recognising and avoiding error in complex situations'.

"... managers need to engage in deeper reflective thinking. This is particularly true about how they manage change. An understanding of systems thinking is necessary to succeed at this. "

http://c.ymcdn.com/sites/www.project...s/mayjun09.pdf

Last edited by alf5071h; 18th Sep 2016 at 16:31. Reason: Typo
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Old 18th Sep 2016, 10:57
  #1629 (permalink)  
 
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Some good thoughtful posts.

Given that windshear was present, it would have also been turbulent, and one thing that I have never seen addressed is our use of a only a single hand to fly when flying a complex manouver.

It is SOP to have one hand on the thrust levers and one on the yoke/side-stick on finals, but of course this means that only half of one's brain is being used to manipulate the attitude control of the aircraft. {The human brain is configured such that only the right side of the brain controls the left hand and vice-versa}. Add to this, the majority of people are right handed. So when a person flies from the left seat, as well as only using half their brain capacity, they are most likely to be using their non-dominant hand/brain side to operate the attitude controls in what can be a highly dynamic, quickly changing scenario. The other half of their hand/brain control capacity is simply static on the thrust levers.

I can imagine that given a turbulent approach, the Captain might have needed/wanted much finer control on the yoke and therefore having pressed TOGA, I wonder did he then take his right hand off the thrust levers and onto the yoke so all of his brain and both hands were being used to control the plane - trusting that the autothrust would do what he wanted? With moving thrust levers, there is perhaps less reliance given to monitoring the engine N1/EPR gauges, and so the lack of spool up might have been missed by both pilots?

If all this was the case it should have led to a much earlier go-around decision of course, but as I say, I have never seen this single handed business discussed.

(Obviously, one can only have one hand on a side-stick, but the FBW computers do at least assist the pilot, which mitigate this to some extent)

As many of us keep saying; the answer has to be better training.

We are always told how we must fly but one thing that might be beneficial might be to give us scenarios in the SIM that will deliberately lead to bad things happening? For example, landing on a short runway with a speed of +10kts leading to an over-run. The pilots would be told what was going to happen, and no jeapordy would be invoked, but it might be useful to actually experience the consequences of mis-handling. Otherwise, as long as we are there or thereabouts within the limits, we pass our SIM check and maybe never really appreciate what could happen if we went outside limits.

In the SIM recently I was given the scenario of AF447 - without being told it was going to happen, and the Captain was in on the plan, so he did/said nothing. To my absolute horror, I did pretty much the same thing as those AF pilots - (although I thought it was a Vaplha prot issue). Now obviously, I know the unreliable speed drill, but this was so subtle that I did not recognise it as such. Having had it demonstrated to me in that very dramatic way it will stay with me for ever and if I ever see that situation developing, I will know exactly what to do. (One thing that blocked my thinking was the very loud and persistent overspeed alarm, which drowned out the "stall stall stall")

My point is that any amount of words on a page about the incident and how to deal with unreliable speed etc, did not help me, but actually seeing and experiencing how subtle it can be and how it can go wrong first-hand has gone deep into my brain.
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Old 18th Sep 2016, 11:00
  #1630 (permalink)  
 
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I did a touch-and-go once with passengers on board (737). At 30 feet we got a windshear warning. Winds were gusty, and coming over a line of trees ajacent to the runway. So when we were below the tree line, a windshear warning was issued.

You did't read about it in the papers beacause I firewalled the engines. We very smoothly touched the runway, and off we went.

The most striking thing that I remember about this incident, was the absolute backbone instinct that drove me to firewall the thrust levers.

That was't the chimp in me. That was the fish ancestor trying to escape from danger.
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Old 18th Sep 2016, 13:12
  #1631 (permalink)  
 
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Originally Posted by 4468
It's nothing to do with manual flying skills per se! It's about practicing THIS PARTICULAR MANOUVRE!
I don't agree. Why do you think the FO called "speed"? Because he did what a current, practised pilot who is used to looking at his instruments for survival ie when handflying does. If one is well-versed in flying the aeroplane, even if one makes an almighty stuffup like hit the TOGA and not realise nothing happened because it was less than 5ft, he will shortly after notice the speed dropping off then instinctively work out there's no power.

I do agree that this particular manoeuvre has to be practised, but the fundamental underlying process/skill for any of our activities must be ability and currency on flying the aeroplane.
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Old 18th Sep 2016, 13:22
  #1632 (permalink)  
 
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The comment "chimp choosing wrong motor action in this scenario". Very valid. There was also a comment about 3 GA scenarios. The clue what do in which is in the small print read many moons ago, stored in the deepest longterm memory at the rear of the brain, and hopefully can be dragged forward in the split second it is needed years later. The standard SOP GA from Minima is in the current memory at the front of the brain, so no surprise this erroneous action was chosen.

The question was solutions.
1.Training, repetitive recurrency exposure: all good, but how often will it be used; how likely? Thus many HOT's would deem the time not best spent.
2. Make all GA's manual thrust = system redesign. Thus there is no choice & no doubt.
3. Change and re-enforce SOP's for PF to follow through TL's on any GA and for PM to verify as their priority. FCTM & company SOP's.

Every GA is the same motor action. No choice, no excisions, no doubts. JUST DO IT. 'Nike'.

Opinions?
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Old 18th Sep 2016, 13:47
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Every GA is the same motor action. No choice, no excisions, no doubts. JUST DO IT. 'Nike'.
I don't think they are. Take that 777 GA video from 12" off the ground (or did they touch down?) many pages back http://www.pprune.org/rumours-news/5...ml#post9476561. That is nowhere near a "normal" goaround: fly level with the ground/touchdown attitude at zot feet, with full power coming on, then gently rotate away so you don't bang the tail. That is not a motor action. An EGPWS escape is a motor action, processing a set of steps. This prang, I suspect, will be something that requires far more skill than a simple push n pull.

Last edited by Capn Bloggs; 18th Sep 2016 at 14:59.
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Old 18th Sep 2016, 16:27
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I tend to go with 4468. Lack of manual skill has nothing to do with this accident which was due lack of knowledge of automation. Since absence of thrust caused the problem everybody is forgetting that GO levers have another function, to give FD guidance for GA. If you execute all go rounds manually then the FDs remain in approach mode they need to be ignored. Not a good way to fly, on another day in poor visibility some one may go down following them (already happened thrice in airbus). GA procedure after touch down is an exception and should be treated as such. The only remedy for lack of knowledge is to learn, practice and revise during every briefing. If you brief the GA procedure after touch down the PM will make sure you do it.
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Old 18th Sep 2016, 16:46
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If you brief the GA procedure after touch down the PM will make sure you do it.
How much stuff are you ready to brief on the line ... ?
Far too much talking already.
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Old 18th Sep 2016, 17:16
  #1636 (permalink)  
 
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Bloggs: This prang, I suspect, will be something that requires far more skill than a simple push n pull.

Of course: we are in violent agreement.

Maybe I expressed myself badly. My intention was to suggest a discussion about whether the basic foundation of a GA should be the same, i.e. advance thrust manually (technically necessary) or follow the thrust levers to ensure movement (SOP). 4468 was discussing motor skills and muscle memory, and how it is possible to select the wrong one. I'm opening a discussion to remove that doubt. I know the pitch control is variable; that is piloting and a/c control; it is not thrust control. The root fault here seems to be lack of thrust. I'm looking at the root cause of why no thrust and considering simple options so it does't happen again.
Pushing TOGA causes an input into FD. That is pitch guidance. Let's separate pitch guidance & thrust application. On a B737NG, single channel ILS with AT, pushing TOGA disconnects AP but not AT; so PF needs to control pitch. However, all my previous airlines had PF SOP as following through on TL's. Does EK or Boeing have a follow through SOP, or is the SOP press & forget?
My question was regarding thrust, not a/c speed or pitch control: if every GA needed manual thrust, or follow through, would this type of confused accident happen again?
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Old 18th Sep 2016, 18:08
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I don't think that the issue in this case is as complex as some are indicating. You basically need two things immediately when performing a go-around - a positive pitch attitude (initially around 15 NU for this aircraft) & lots of thrust. This guy knew he needed those two things. He pitched the aircraft NU & 'called' for the power by pressing TOGA. What happened was an over-reliance on automation caused him to miss the fact that the automation had not delivered what he wanted. He wouldn't have got FD commands either, he was obviously used to setting a target pitch & going from there. Perhaps he was just starting to realize that he didn't have FD commands for the GA when it all started to go wrong.

He seems to me that he knew how to fly the required maneuver. He was just too trusting of the automation.
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Old 18th Sep 2016, 19:33
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He seems to me that he knew how to fly the required manoeuver. He was just too trusting of the automation.
No. He didn't know how to execute a go around after touch down. He wasn't too trusting the automation and was let down but expecting the automation to do something that it wasn't designed to do and was not going to happen. He needed to know that triggering go levers will neither get the thrust nor the FDs. Thrust had to be manually obtained and just sufficient rotation to avoid nose wheel touch down without FD guidance had to be obtained. 15 degrees would have caused a tail strike. There was no need to retract the gear before checking thrust. If gear was not retracted the aircraft may not have been destroyed.

Last edited by vilas; 18th Sep 2016 at 19:48.
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Old 18th Sep 2016, 19:36
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He pitched the aircraft NU & 'called' for the power by pressing TOGA.
For now, nothing to state in the report either TOGA switches has been pressed ...
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Old 18th Sep 2016, 20:20
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To me that is pretty key. The report neither says the pilots did or did not press TOGA. I guess we need the full report to appear, assuming that a press (that does nothing) if the wheels were grounded will be logged in the FDR. If they did press TOGA then we enter a world of the training/automation blame game, if not then it is a simple human error.

However is there a GA that doesn't require a whole boot full of thrust? And is there an aircraft in the world that doesn't respond to the throttles being jammed forwards - if so, why not make firewall the thrust the very first item on any go around, on any aircraft? It may be that the automatics on some aircraft will pull the throttles back since they still think they are landing, but at least if you forget you have that problem from 400 feet not 85.

Either that or a big red 'HAL get me outta here' mushroom button on the centre console to fly a pre set escape route... HAL does not forget to set thrust, retract flaps, avoid striking the tail, bring the gear up or miss the mountain. Of all the stages of flight where a machine should be able to do well, and where humans do badly due to high stress, this is a standout one.

Last edited by Snyggapa; 18th Sep 2016 at 22:15. Reason: Typo
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