AA757 Near Stall - Recovery Caused Injuries
I think that it took four years to produce this report as bordering on negligence. All FDR/CVR, pilots survived intact and an investigation with something to learn from it couldn't be produced in a few weeks/months?
And yes we are in a parallel universe where pilots cannot pilot anymore.
And yes we are in a parallel universe where pilots cannot pilot anymore.
As a flight engineer I needed to be type rated for the aircraft I was working, same with the pilots but why would the flight instructor not need to be type rated?
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A) An overload of regulations/must-do's, with the consequence that things start falling off the table.
B) More and more an emphasis on "regulations and must-do's", with the consequence, that pilots become hesitating to "follow their guts" to solve an issue.
This not so much being a flying industry only issue. It happens everywhere, that people no longer dare to solve an issue, but revert to "not in my playbook, so I don't (or I am not allowed to) do".
An example of what happened some years ago in GA, with a C172, a highly experienced pilot. Flying at 2000ft towards a controlled airport, clouds come in unexpectedly with heavy winds and the aircraft getting "VFR on top". The airport was still visible in perfect VFR weather. So, the best option would have been, stay VFR on top, IE fly higher than the normal height for the VFR route in the controlled airspace to the airport. But, that implies, asking permission, and investigations, and potentially a fine. The pilot decided to descent through IMC to expected VDR weather below the clouds. Unfortunately, the clouds were fog, all the way to the ground and the aircraft did a CFIT (and, explicitly, no Loss of Control). 4 People dead, just because the pilot selected to do what could not be registered as an offense and avoiding getting asked nasty questions, etc.
This. Lawyers and managers in cockpits.
This thread is an example of how language can frame issues, biasing opinion, leading inappropriate conclusions.
The thread title ‘757 Near Stall’ does not relate to the safety investigation referring to speed monitoring.
Total flight hours is falsely equated to experience, whereas experience relates to prior exposure to a situation or similar, and embedding that in memory with focussed learning, understanding and relevance.
The outcome of this event was success; a safe landing. The safety issue is with speed awareness and subsequent flight handling.
Previous incidents and more general speed-AT issues suggests some auto-flight complacency. If repeated events are specific to an aircraft type then consider the technology - dated certification, assess if this is compatible with modern environment, training; consider modification. Crews cannot be expected to manage every system weaknesses in every situation, all of the time.
Re recovery; with situation recognition the injuries resulted from aggressive control. With hindsight this maybe judged inappropriate, but the reaction could have been ingrained by training and SOPs requiring urgent aggressive response to low speed or upset events. The point at which the stall / upset recovery no longer applies has to be judged by the crew, but without alternative other than to ‘fly the aircraft’. Judgements are relative, they are not clearcut decisions defined by procedure, and thus should not be criticised after the event. The crew acted as they saw the situation and as required by their recall of training; the points of safety involve what contributed to the situation and crew behaviour.
[For further debate, would a correct, aggressive upset recovery from wake turbulence, with cabin injury, be assessed in the same manner.]
If the satisfaction of blame is still required then consider how crews are trained for unexpected situations, how they are expected to manage technological deficiencies - situations which have probably been seen by others beforehand, but not reported. A professional approach seeks perfection, but rarely acknowledges the human limitation, that we have done our best but circumstance outwitted us.
The thread title ‘757 Near Stall’ does not relate to the safety investigation referring to speed monitoring.
Total flight hours is falsely equated to experience, whereas experience relates to prior exposure to a situation or similar, and embedding that in memory with focussed learning, understanding and relevance.
The outcome of this event was success; a safe landing. The safety issue is with speed awareness and subsequent flight handling.
Previous incidents and more general speed-AT issues suggests some auto-flight complacency. If repeated events are specific to an aircraft type then consider the technology - dated certification, assess if this is compatible with modern environment, training; consider modification. Crews cannot be expected to manage every system weaknesses in every situation, all of the time.
Re recovery; with situation recognition the injuries resulted from aggressive control. With hindsight this maybe judged inappropriate, but the reaction could have been ingrained by training and SOPs requiring urgent aggressive response to low speed or upset events. The point at which the stall / upset recovery no longer applies has to be judged by the crew, but without alternative other than to ‘fly the aircraft’. Judgements are relative, they are not clearcut decisions defined by procedure, and thus should not be criticised after the event. The crew acted as they saw the situation and as required by their recall of training; the points of safety involve what contributed to the situation and crew behaviour.
[For further debate, would a correct, aggressive upset recovery from wake turbulence, with cabin injury, be assessed in the same manner.]
If the satisfaction of blame is still required then consider how crews are trained for unexpected situations, how they are expected to manage technological deficiencies - situations which have probably been seen by others beforehand, but not reported. A professional approach seeks perfection, but rarely acknowledges the human limitation, that we have done our best but circumstance outwitted us.
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This incident has two straight forward reasons. First is ignorance of the the not so smart or perhaps not very necessary THR HOLD function. And second is lack of proper instrument scan. Speed and altitude requires frequent look over whether with or without AP. A320 accident in 1980 Bangalore is simply mirror reflection of the SFO. Airbus ATHR is non moving thrust levers while B777 has tactile feed back through moving throttles but failed to notice that they were at idle all along. Both accidents nobody monitored FMA or speed. In Bangalore speed reached 26kts below Vapp, in SFO it reached 31kts below Vapp. with similar results.
vilas,
First how can you explain knowledge of the extent or quality of the crews ‘ignorance’.
Unlikely, pure speculation based on your assessment of the event with hindsight. False reasoning from the outcome, backward to deduce cause … Not so.
How many similar events have been encountered without a problem.
Second, how can you know the quality of the crews instrument scan; presuming that you were not there nor have discussed the issue with the crew.
Hindsight bias; https://thedecisionlab.com/biases/hindsight-bias
Individual effects -
… If we look back at past decisions and conclude that their consequences were indeed known to us at the time (when they weren’t), then it makes sense that we will overestimate our ability to foresee the implications of our future decisions. This can be dangerous, as our overconfidence may lead us to take unnecessary risks. …
Also see the related biases: Regret Aversion, Cognitive Dissonance, Dunning–Kruger Effect
First how can you explain knowledge of the extent or quality of the crews ‘ignorance’.
Unlikely, pure speculation based on your assessment of the event with hindsight. False reasoning from the outcome, backward to deduce cause … Not so.
How many similar events have been encountered without a problem.
Second, how can you know the quality of the crews instrument scan; presuming that you were not there nor have discussed the issue with the crew.
Hindsight bias; https://thedecisionlab.com/biases/hindsight-bias
Individual effects -
… If we look back at past decisions and conclude that their consequences were indeed known to us at the time (when they weren’t), then it makes sense that we will overestimate our ability to foresee the implications of our future decisions. This can be dangerous, as our overconfidence may lead us to take unnecessary risks. …
Also see the related biases: Regret Aversion, Cognitive Dissonance, Dunning–Kruger Effect
Did they get a stick-shaker, or did the pilot just realize they were going way to slow?
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vilas,
First how can you explain knowledge of the extent or quality of the crews ‘ignorance’.
Unlikely, pure speculation based on your assessment of the event with hindsight. False reasoning from the outcome, backward to deduce cause … Not so.
How many similar events have been encountered without a problem.
Second, how can you know the quality of the crews instrument scan; presuming that you were not there nor have discussed the issue with the crew.
Hindsight bias; https://thedecisionlab.com/biases/hindsight-bias
Individual effects -
… If we look back at past decisions and conclude that their consequences were indeed known to us at the time (when they weren’t), then it makes sense that we will overestimate our ability to foresee the implications of our future decisions. This can be dangerous, as our overconfidence may lead us to take unnecessary risks. …
Also see the related biases: Regret Aversion, Cognitive Dissonance, Dunning–Kruger Effect
First how can you explain knowledge of the extent or quality of the crews ‘ignorance’.
Unlikely, pure speculation based on your assessment of the event with hindsight. False reasoning from the outcome, backward to deduce cause … Not so.
How many similar events have been encountered without a problem.
Second, how can you know the quality of the crews instrument scan; presuming that you were not there nor have discussed the issue with the crew.
Hindsight bias; https://thedecisionlab.com/biases/hindsight-bias
Individual effects -
… If we look back at past decisions and conclude that their consequences were indeed known to us at the time (when they weren’t), then it makes sense that we will overestimate our ability to foresee the implications of our future decisions. This can be dangerous, as our overconfidence may lead us to take unnecessary risks. …
Also see the related biases: Regret Aversion, Cognitive Dissonance, Dunning–Kruger Effect
I've been wondering the same - 186 kts doesn't sound dangerously slow to me. More like the PF was distracted then startled when he realized they were approaching stall and shoved the wheel forward.
Did they get a stick-shaker, or did the pilot just realize they were going way to slow?
Did they get a stick-shaker, or did the pilot just realize they were going way to slow?
That's a safety issue.
Whilst I think Alf understands the complexity behind the human condition better than most; vilas has a simple but correct point - if Speed decays 20-30 knots below Vapp then either the pilots are not scanning/observing the speed or they are and don't comprehend the situation.
One is closer to negligent behaviour and more straightforward and the other is much more complex and involves training, recruitment, fatigue, SOPs, CRM and so on.... So it really then depends on where you place the crew in any incident on that scale and more importantly where their management places them.
One is closer to negligent behaviour and more straightforward and the other is much more complex and involves training, recruitment, fatigue, SOPs, CRM and so on.... So it really then depends on where you place the crew in any incident on that scale and more importantly where their management places them.
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I'm not sure how adding another instrument to the panel would of solved the problem
Agree. A lack of instrument scan, simple as that. Pilot 101.
This crew obviously did not monitor their airspeed. Had they noticed the decaying speed, all they had to do in a Boeing - in any aircraft for that matter - was manually push the thrust levers forwards.
If the speed starts dropping, I glance at the engine N1 or EPRs, and I expect to see the auto-thrust bring the engines up to correct it. If auto-thrust doesn't react I do something about it.
If the automatics are not doing what is required, you step in and reselect or take over.
Unless, maybe the thrust levers both became physically jammed at idle and both crew struggled to release them as the speed decayed, but we haven't heard anything along these lines.
This crew obviously did not monitor their airspeed. Had they noticed the decaying speed, all they had to do in a Boeing - in any aircraft for that matter - was manually push the thrust levers forwards.
If the speed starts dropping, I glance at the engine N1 or EPRs, and I expect to see the auto-thrust bring the engines up to correct it. If auto-thrust doesn't react I do something about it.
If the automatics are not doing what is required, you step in and reselect or take over.
Unless, maybe the thrust levers both became physically jammed at idle and both crew struggled to release them as the speed decayed, but we haven't heard anything along these lines.
Seems a gentle forward push along with advancing the thrust levers would have been more than sufficient to prevent the aircraft falling out of the sky.