Emirates B777 gear collapse @ DXB?
notapilot, The objective of my post #1475 was to generate thought about contributing factors, it was not intended to preempt any report. Actually this type of thinking does not require a report, just a trigger to consider safety issues from a range of perspectives, individual, operator, manufacturer, or regulator, irrespective of their involvement in this accident. It would be even more beneficial if we can suppress hindsight bias, avoid using outcome knowledge to infer cause.
Many posts continue to focus on training and procedures; this line of thought still infers blame; the human is broken, fix it, like mending a machine.
The alternative requires industry to reconsider safety thinking. This type of accident isn't caused, it emerges from 'normal' operations; they are surprising events, particularly to management, manufacturers, and regulators, because the overall system did not work as intended - our assumptions about human performance in the context of the man-machine-environment, were incorrect. In effect these types of accident are designed into the system, again, by all of us.
Lonewolf, pitch+power=, yes a classic, but if the context of operation is changed (man-machine-environment) then the value of such fundamentals can also change, even weakened beyond relevance. Does the industry 'know' if pilots look at pitch vs using FDs. Similarly with dependency on auto-thrust, 'power' may not have the same piloting relationship.
C_Twitcher, yes the latent 'factor' may still be lurking; even though we have knowledge of this accident, the risk of a further event is unchanged.
Re RAAS, it's now several hours since posting a RAAS question in Tech Log. Is the absence of replies indicative of the level of system knowledge for a major safety system installed in many aircraft, ... or does limited knowledge generate safety weakness if inappropriately employed.
Many posts continue to focus on training and procedures; this line of thought still infers blame; the human is broken, fix it, like mending a machine.
The alternative requires industry to reconsider safety thinking. This type of accident isn't caused, it emerges from 'normal' operations; they are surprising events, particularly to management, manufacturers, and regulators, because the overall system did not work as intended - our assumptions about human performance in the context of the man-machine-environment, were incorrect. In effect these types of accident are designed into the system, again, by all of us.
Lonewolf, pitch+power=, yes a classic, but if the context of operation is changed (man-machine-environment) then the value of such fundamentals can also change, even weakened beyond relevance. Does the industry 'know' if pilots look at pitch vs using FDs. Similarly with dependency on auto-thrust, 'power' may not have the same piloting relationship.
C_Twitcher, yes the latent 'factor' may still be lurking; even though we have knowledge of this accident, the risk of a further event is unchanged.
Re RAAS, it's now several hours since posting a RAAS question in Tech Log. Is the absence of replies indicative of the level of system knowledge for a major safety system installed in many aircraft, ... or does limited knowledge generate safety weakness if inappropriately employed.
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Globefish & Alf: and others who have commented, not just on this topic, but in general. IMHO it is the case that in some scenarios, especially with large startle factor, SOP's don't always come to your aid. By that I mean this: you as a pilot feel the need to abort a landing. It could be at minima, close to the ground or on the ground. One will have more of a startle factor than another. One will have been briefed more than the other. One will have been practiced more than the other.
If you execute the low startle factor well briefed manoeuvre it is likely to go OK. The SOP's will kick in. You have spare capacity to think and be aware of what's going on. Both of you know & understand the scenario.
Now you end up in one of the other scenarios where you need to think as a basic pilot, but are slowed down by trying to remember the SOP that doesn't seem to quite fit the scenario. It would be easy to jumble up the sequence or forget items. You try, because in the sim you are berated if your don't follow SOP's. Your airmanship brain is confused because you feel the need for discretion, but hesitate and try to spit the correct words out and do the correct actions.
Go back to being a basic pilot. A GA in a Cessna is similar to an all engine a/c; i.e. no rudder necessary. It's power up, speed up, nose up, gear up. The brain can stay clean & clear. It's called KISS.
I wonder if the rigid SOP's have made it difficult, unnecessarily?
I have flown for one airline whose GA SOP call outs & actions make me need to go to RADA for a week. Now transpose them to this scenario. I hate to think.
I've also flown for airlines whose dogma was "the SOP's will keep you safe." Hm???
If you execute the low startle factor well briefed manoeuvre it is likely to go OK. The SOP's will kick in. You have spare capacity to think and be aware of what's going on. Both of you know & understand the scenario.
Now you end up in one of the other scenarios where you need to think as a basic pilot, but are slowed down by trying to remember the SOP that doesn't seem to quite fit the scenario. It would be easy to jumble up the sequence or forget items. You try, because in the sim you are berated if your don't follow SOP's. Your airmanship brain is confused because you feel the need for discretion, but hesitate and try to spit the correct words out and do the correct actions.
Go back to being a basic pilot. A GA in a Cessna is similar to an all engine a/c; i.e. no rudder necessary. It's power up, speed up, nose up, gear up. The brain can stay clean & clear. It's called KISS.
I wonder if the rigid SOP's have made it difficult, unnecessarily?
I have flown for one airline whose GA SOP call outs & actions make me need to go to RADA for a week. Now transpose them to this scenario. I hate to think.
I've also flown for airlines whose dogma was "the SOP's will keep you safe." Hm???
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A nice handy TOGA button that sometimes doesn't work is something to be very wary of.
Let me put this in perspective: My multi-engine experience was in P-3s. The P-3 has TWO complete sets of power levers, one set each for the pilot (1P) and the copilot (2P). The flight engineer (FE) sits in a seat facing forward just aft of the center pedestal and has access to BOTH sets of power levers. The arrangement means the P-3 had a "voice activated" autothrottle system. By this I mean that it was routine for the pilot at the controls to call out "horsepower XXXX" to the FE. The pilot at the controls has his hand on the power levers on his side (he "rides" the power levers and can feel what the FE is doing) while the FE uses the power levers on the other side to set the desired power. The pilot not at the control places his hand on the pedestal just behind the levers the FE is operating as back up (he "follows" the power levers). In other words, it was SOP that THREE sets of hands are feeling the advance of the power levers, and at least two sets of eyes are checking the torquemeter gauge to verify that power is what it should be.
For me, one pilot riding the power levers while the other is following the power levers while the autothrottle (either flesh and blood or electronic) is engaged is instinctive. Thus it is unfathomable to me that the pilots in this incident were not aware that the autothrottle system for whatever reason was not advancing the power levers, whether that was by design, due to system failure, or due to leprechauns dancing on the center pedestal. But this is because of the training I received and the SOP we followed. To me, it is clear that the training these pilots received and the SOP they were required to follow set them up for failure. And to me, that's very sad. And since managers are involved, I must wonder how long it will take to correct this clear deficiency in training and SOP.
Last edited by KenV; 13th Sep 2016 at 16:33.
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Since Cranbrook, the thrust reverser systems have been designed to keep the isolation valve open until the reverser has completely stowed and locked, and the actuators are sized to insure they can overcome any aerodynamic forces at high engine power.
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It is reasonably clear that Boeing recommended go around procedure after touch down was not followed where pilot needs to apply TOGA manually and initiate climb without FDs. why wasn't it done? Man, machine, environment. It could be one time error, inadequate training of this particular situation or lack of required knowledge of automation. Machine, GA mode could be improved. Environment? high temperature, moderate wind shear, demanding but not so hostile.We have to wait for full report.
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The system is designed to make sure the reversers completely stow.
td, this is not entirely correct, as the loss of Lauda Air Flight 004 (the first 767 loss) sadly proved. That was the seminal event that resulted in a truly fail-safe thrust reverser design.
How come airbus doesn't agree with that? After all airbus doesn't manufacture engines. reverse is full stop for airbus.
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tdracer
Your post is misleading. It is possible off course to abort landing after thrust reverser deployment provided you have sufficient runway and both reverser stow properly. But it is dangerous because there is always the possibility of thrust reverse misbehaving while stowing and that is the precise reason for calling it a full stop. Air India express B737 800 crash in 2010 at Mangalore the inquiry report states Boeing SOP which forbids GA after thrust reverse deployment. The reason you are giving is also dangerous because how a pilot will judge that you safely get airborne over another aircraft. In Mangalore crash the test pilot stated the aircraft would have stopped in the available distance but the go round caused it to hit the obstruction at the end of the runway. Not only Airbus but Boeing also forbids it.
Your post is misleading. It is possible off course to abort landing after thrust reverser deployment provided you have sufficient runway and both reverser stow properly. But it is dangerous because there is always the possibility of thrust reverse misbehaving while stowing and that is the precise reason for calling it a full stop. Air India express B737 800 crash in 2010 at Mangalore the inquiry report states Boeing SOP which forbids GA after thrust reverse deployment. The reason you are giving is also dangerous because how a pilot will judge that you safely get airborne over another aircraft. In Mangalore crash the test pilot stated the aircraft would have stopped in the available distance but the go round caused it to hit the obstruction at the end of the runway. Not only Airbus but Boeing also forbids it.
What's misleading? Boeing procedures prohibit aborting a landing after t/r deployment. But we design the system so if they do, they won't crash because of the reverser system (no guarantee that they won't still hit the obstacle). Cranbrook crashed because the aircraft became airborne before the thrust reversers were fully stowed, and one re-deployed - had the reverser not re-deployed, they wouldn't have crashed and 41 people wouldn't have died.. We don't want that to happen again so we design the t/r to fully stow even if the aircraft becomes airborne again before the reverser is fully stowed.
Yes, it is an unapproved, dangerous maneuver. So is running into a snowplow or another aircraft at 100 knots.
Yes, it is an unapproved, dangerous maneuver. So is running into a snowplow or another aircraft at 100 knots.
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"pilot needs to apply TOGA manually"
Sorry Vilas @1510, TOGA is an autothrottle mode not an action.
Manual power lever selection, firewall the throttles, punch the instrument panel, slam the lollipops forward - these are actions.
"TOGA + check thrust" is futile if the mode is inhibited as it will be if the aircraft is on the ground. SQ 327 at Munich demonstrated this. After several attempts to get TOGA selection to deliver the thrust he gave up and tried to stop on the runway.
Any SOP that calls for TOGA selection in this situation , as opposed to a command to apply full power manually, is dangerously misleading as the pilot might reasonably expect the power to be applied automatically and may be be distracted when it isn't.
Sorry Vilas @1510, TOGA is an autothrottle mode not an action.
Manual power lever selection, firewall the throttles, punch the instrument panel, slam the lollipops forward - these are actions.
"TOGA + check thrust" is futile if the mode is inhibited as it will be if the aircraft is on the ground. SQ 327 at Munich demonstrated this. After several attempts to get TOGA selection to deliver the thrust he gave up and tried to stop on the runway.
Any SOP that calls for TOGA selection in this situation , as opposed to a command to apply full power manually, is dangerously misleading as the pilot might reasonably expect the power to be applied automatically and may be be distracted when it isn't.
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How many hull losses of perfectly flying aircraft did we have now due to inability to observe / control the thrust / airspeed?
We need a clear policy worldwide: manual flight equals manual thrust, no exceptions in normal operation allowed. Autothrust only with autopilot on or under technical abnormals if judged helpful by the crew. That would give pilots their scanning and their muscle memory back. It would not cost a penny, but save us the next hull loss due to no thrust in the wrong moment.
Then Boeing should think about redesigning their thrustlevers, remove these TOGA-buttons and include mode-selection in the thrust lever itself like Airbus does it.
It really would not be that difficult.
We need a clear policy worldwide: manual flight equals manual thrust, no exceptions in normal operation allowed. Autothrust only with autopilot on or under technical abnormals if judged helpful by the crew. That would give pilots their scanning and their muscle memory back. It would not cost a penny, but save us the next hull loss due to no thrust in the wrong moment.
Then Boeing should think about redesigning their thrustlevers, remove these TOGA-buttons and include mode-selection in the thrust lever itself like Airbus does it.
It really would not be that difficult.
At my employer, PF does NOT operate reversers! That is a job for PM. That simple fact allows me to pre-brief that PF does not remove their hand from the thrust levers unless they are happy we can stop, AND PM does not select reverse unless they are also happy we can safely stop. Either pilot can call go-around. We both have a very immediate investment, and clear responsibility, in the landing! ONLY when reverse is selected, are we committed to completing the landing! Not before.
First of all, there is a strong risk of confusion when both pilots are handling the controls at the same time. One on the flight controls and the other on engine controls. By that I mean the reverse thrust levers are controls in the sense of directional control. if you don't believe that, then suggest you read the Boeing 737 FCTM on landing on slippery runways in a crosswind where weather cocking after touch down can cause a problem unless careful use of reverse is made. The heading of that particular page is "Reverse Thrust and Crosswind (All engines). A diagram is shown as a way of explanation. The text then states (quote):
"This figure shows a directional control problem during a landing rollout on a slippery runway with a crosswind. As the airplane starts to weathervane into the wind, the reverse side force component adds to the crosswind component and drifts the airplane to the downwind side of the runway. Also, high braking forces reduce the capability of the tires to corner.
To correct back to the centreline, release the brake and reduce reverse thrust to reverse idle. Releasing the brakes increases the tire-cornering capability and contributes to maintaining or regaining directional control. Setting reverse idle reduces the reverse side force component without the requirement to go through a full reverser actuation cycle. Use rudder pedal steering and differential braking as required, to prevent over correcting past the centreline. When directional control is maintained and the airplane is correcting toward the runway centreline, apply maximum braking and symmetrical reverse thrust to stop the airplane. Use of this technique increases the required landing distance." Unquote.
It should be perfectly straight forward for the PF to land the aircraft and apply his own reverse thrust. There is nothing complicated about that. Any directional control issues will be immediately apparent and handled appropriately by the PF including the reverse thrust. No words have to be exchanged between PF and PM.
The possibility of the PM missing or misinterpreting any instructions from the PF if the PM is in charge of the reversers, is minimised. That is because the PF is handling the reversers. The last thing anyone needs is hands in all directions during the landing run with someone on the thrust levers and someone else on the reverse thrust levers.
Last edited by Centaurus; 14th Sep 2016 at 02:30.
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c.j.shrimpton
TOGA is not only a FD mode but also can refer to a thrust setting FMA would indicate that. The actions you mention is the way to get that thrust. Even if FDs are NA you may still call for TOGA thrust.
TOGA is not only a FD mode but also can refer to a thrust setting FMA would indicate that. The actions you mention is the way to get that thrust. Even if FDs are NA you may still call for TOGA thrust.
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Centaurus
4468 flies for company that has many own procedures that even manufacturer will frown. Any one who doesn't work there is not likely to find much merit in them and the argument will go on and on. I am happy he supports FMA calls because on another thread there was vehement opposition to FMA calls despite me quoting three incidents that could have been accidents. Another example of an airline that thinks they know better. When B777 go around procedure categorically states that after touch down pilot needs to set TOGA thrust manually not doing so is definitely pilot error. Some things can be practiced, some demonstrated and some can be effectively explained even in a class room. We lament about lack of manual flying skills but more and more incidents are taking place that show inadequate knowledge of automation as to what it does and what it won't. Proper goal oriented training can definitely improve the situation. A few things can be done in more than one way and both ways work under normal circumstances but one of them can set you up for an incident when under pressure. Existing data of incidents/accidents and manufacturers advice should be sought while making procedures.
4468 flies for company that has many own procedures that even manufacturer will frown. Any one who doesn't work there is not likely to find much merit in them and the argument will go on and on. I am happy he supports FMA calls because on another thread there was vehement opposition to FMA calls despite me quoting three incidents that could have been accidents. Another example of an airline that thinks they know better. When B777 go around procedure categorically states that after touch down pilot needs to set TOGA thrust manually not doing so is definitely pilot error. Some things can be practiced, some demonstrated and some can be effectively explained even in a class room. We lament about lack of manual flying skills but more and more incidents are taking place that show inadequate knowledge of automation as to what it does and what it won't. Proper goal oriented training can definitely improve the situation. A few things can be done in more than one way and both ways work under normal circumstances but one of them can set you up for an incident when under pressure. Existing data of incidents/accidents and manufacturers advice should be sought while making procedures.
Controversial, moi?
We need a clear policy worldwide: manual flight equals manual thrust, no exceptions in normal operation allowed.
TOGA is not only a FD mode but also can refer to a thrust setting FMA would indicate that.
Originally posted by vilas
When B777 go around procedure categorically states that after touch down pilot needs to set TOGA thrust manually not doing so is definitely pilot error.
When B777 go around procedure categorically states that after touch down pilot needs to set TOGA thrust manually not doing so is definitely pilot error.
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@alf5071h
Most airlines learn from their own and others mistakes. No one will wait for the opinion of state of registrar to ICAO.
15 min location reporting(MH370) and second authorized person in flight deck(4U9525) are such examples.
Most airlines learn from their own and others mistakes. No one will wait for the opinion of state of registrar to ICAO.
15 min location reporting(MH370) and second authorized person in flight deck(4U9525) are such examples.
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After Sully a few airlines got in on the act and gave their guys double flameouts to glide landings during recurrency training. This was a non-fatal accident. After Air Peru B757 had its static ports blocked up and crashed I don't remember hearing too much about this scenario being introduced into recurrency training. It was a survivable accident, albeit very difficult and requiring much skill and airmanship; but isn't that the point of recurrence training, to learn from other's mistakes? Which event is the more likely to occur: loss of static or double engine failure? So which recurrency training would be more productive in preventing fateful accidents?
I wonder how many airlines will now introduce a proper rejected landing in their recurrency training, or even type rating? Will it replace the 50' ground round LST mandatory item via XAA stipulation? IMHO it should, or even be an addition.
I wonder how many airlines will now introduce a proper rejected landing in their recurrency training, or even type rating? Will it replace the 50' ground round LST mandatory item via XAA stipulation? IMHO it should, or even be an addition.