Turkish airliner crashes at Schiphol
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S.F.L.Y.
These things are rarely 'black and white'.
Fuxxackes, they'd be going around all bloody day, at airports all over the world if we all took your approach.
Why not just teach the pilots to fly?
Or is it easier to just tell them what button to push!
Having said that, when the report comes out, methinks AMS ATC will get a mention!
These things are rarely 'black and white'.
Fuxxackes, they'd be going around all bloody day, at airports all over the world if we all took your approach.
Why not just teach the pilots to fly?
Or is it easier to just tell them what button to push!
Having said that, when the report comes out, methinks AMS ATC will get a mention!
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Why bother guessing?
Given that the full report should be out soon enough, is there much point to piling up guesses to try and figure out what caused this accident?
Most of us probably would never make jury selection, already having made up our minds about the case before hearing the testimony but that can just be pilots, an opinionated lot in any case. Perhaps that is part of what helps us to go wazzing off through the stratosphere trusting in our wonderful abilities to foresee a happy end to that. In the same way we can be handed a puzzle numerous experts have spent a year trying to solve and just say, "It was because the crew were [insert theory here]," as if that means "case solved." Actually, might it be so that there shall be some stuff in this report we don't know and haven't expected? You know, "expect the unexpected"?
There are all sorts of "tricks of the trade," stuff you learn from flying with other, more experienced pilots or by reading books and articles (as here, even), what we often half-jokingly say is "what you don't learn in flying school." How can one be so sure that someone else, even this crew who died in an accident, had or has "it all wrong"? Often we find it was just one tiny, mistaken detail that was that last, fatal link in an accident chain, the same sort of thing we might also overlook, when the sure way to overlook something is to go around clad in iron self-belief.
If it were just a matter of fixing blame then there would be very little point to publishing accident reports. Of course they don't do that but try to establish causes so that we might want to take a cue from that when posting. Fixing blame is like playing "pin the tail on the donkey," when it's just "game over" once it's pinned. Here we are trying to use this tragedy to keep ourselves in play, just the opposite. There is something in this that goes against human nature, that need to fix blame, so that we really have to work on that.
Most of us probably would never make jury selection, already having made up our minds about the case before hearing the testimony but that can just be pilots, an opinionated lot in any case. Perhaps that is part of what helps us to go wazzing off through the stratosphere trusting in our wonderful abilities to foresee a happy end to that. In the same way we can be handed a puzzle numerous experts have spent a year trying to solve and just say, "It was because the crew were [insert theory here]," as if that means "case solved." Actually, might it be so that there shall be some stuff in this report we don't know and haven't expected? You know, "expect the unexpected"?
There are all sorts of "tricks of the trade," stuff you learn from flying with other, more experienced pilots or by reading books and articles (as here, even), what we often half-jokingly say is "what you don't learn in flying school." How can one be so sure that someone else, even this crew who died in an accident, had or has "it all wrong"? Often we find it was just one tiny, mistaken detail that was that last, fatal link in an accident chain, the same sort of thing we might also overlook, when the sure way to overlook something is to go around clad in iron self-belief.
If it were just a matter of fixing blame then there would be very little point to publishing accident reports. Of course they don't do that but try to establish causes so that we might want to take a cue from that when posting. Fixing blame is like playing "pin the tail on the donkey," when it's just "game over" once it's pinned. Here we are trying to use this tragedy to keep ourselves in play, just the opposite. There is something in this that goes against human nature, that need to fix blame, so that we really have to work on that.
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PJ2, it's not about lecturing, some procedures aren't made to be "challenges". Whatever is the airport, an ILS shouldn't be intercepted this way. In this particular case a go around at 5.5 NM shouldn't be questioned. While there's no doubt that was a decision which the crew failed to make, I'm just highlighting the fact that this type of interception "challenges" are often made at the expense of safety or traffic fluidity (in case of GA).
Taking challenges is one thing, but where do we stop? While we're all supposed to be able to operate as per the rules, we are unequal in front of operational challenges.
By taking the challenge you're just making the ATC comfortable with taking it as a norm, which is not necessarily the most efficient at the end of day.
What are you considering a lecture? I'm sure that discussions about Wx RDR or engine design would be very interesting since some of us have very innovative conceptions which are considered based on experience.
chucks, the interesting part of this discussion isn't about "guessing" or blaming. It's about what can be improving safety, whether or not it directly concerned this particular case.
Taking challenges is one thing, but where do we stop? While we're all supposed to be able to operate as per the rules, we are unequal in front of operational challenges.
By taking the challenge you're just making the ATC comfortable with taking it as a norm, which is not necessarily the most efficient at the end of day.
What are you considering a lecture? I'm sure that discussions about Wx RDR or engine design would be very interesting since some of us have very innovative conceptions which are considered based on experience.
chucks, the interesting part of this discussion isn't about "guessing" or blaming. It's about what can be improving safety, whether or not it directly concerned this particular case.
Last edited by S.F.L.Y; 4th Feb 2010 at 07:41.
SFLY,
Oh dear.
I appreciate that you have little or no civilian experience, but really.
Tricky approaches occur daily. You have to use your skill and experience to manage them. This may include the management of the aircraft, but it may also include other elements such as communication with ATC. If you fail to manage the approach, then there are the 1000' and 500' stable approach checks that mandate a go around in nearly every airline.
This crew of three failed to manage a simple defect, failed to monitor the aircraft on approach, failed to go around off an unstable approach, and failed to handle a low speed recovery.
What we don't know is why, but I hope this will be apparent in the final report and (in particular) the CVR. But in answer to your question to chuks about improving safety - crews should monitor the aircraft and observe the rules (stable approach gates). Simple really.
Oh dear.
I appreciate that you have little or no civilian experience, but really.
Tricky approaches occur daily. You have to use your skill and experience to manage them. This may include the management of the aircraft, but it may also include other elements such as communication with ATC. If you fail to manage the approach, then there are the 1000' and 500' stable approach checks that mandate a go around in nearly every airline.
This crew of three failed to manage a simple defect, failed to monitor the aircraft on approach, failed to go around off an unstable approach, and failed to handle a low speed recovery.
What we don't know is why, but I hope this will be apparent in the final report and (in particular) the CVR. But in answer to your question to chuks about improving safety - crews should monitor the aircraft and observe the rules (stable approach gates). Simple really.
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This crew of three failed to manage a simple defect, failed to monitor the aircraft on approach, failed to go around off an unstable approach, and failed to handle a low speed recovery.
Who told you I have no civilian experience? I've been flying VIPs all around Europe capitals for many years and had my share of tight and rushed vectors (with or without GA). Just like you have 1000' or 500' gates, the FAP is another one which shouldn't be skipped just because you have another one further.
I'm sure you will understand the difference between tricky approaches with or without stretching the rules.
the FAP is another one which shouldn't be skipped just because you have another one further.
Ever been to GVA with your VIPs? And in what aircraft? Intercept from above is the norm.
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Given that this is an open forum and all inputs should be allowed (subject to moderation), why not cut SFLY a little slack here? I have to say his/her responses have been pretty moderate considering the odour that is being thrown.
Many people seem to be obsessed with the obvious conclusion that the crew screwed up, and that all us macho pilots should regularly and routinely accept anything ATC throw at them, just get on with it, silk scarves flying, and that's the end of it.
NO! That is not the end of it. IF (nb the capitals) the vectoring for this crew was outwith the regulations that does have a bearing on the accident (the Swiss cheese?).
We need to look at all the facets of this and all accidents - and PJ's points are most vaild too - as we are moving rapidly towards an aviation period of far less experience of this 'macho' flying that we have had since the Wright Brothers.
Talking Swiss cheeses, I am not aware of having loads of 'above G/S' ILS intercepts at GVA - a few, maybe in probably over 100 approaches. Maybe I just had the energy levels sorted out?
Many people seem to be obsessed with the obvious conclusion that the crew screwed up, and that all us macho pilots should regularly and routinely accept anything ATC throw at them, just get on with it, silk scarves flying, and that's the end of it.
NO! That is not the end of it. IF (nb the capitals) the vectoring for this crew was outwith the regulations that does have a bearing on the accident (the Swiss cheese?).
We need to look at all the facets of this and all accidents - and PJ's points are most vaild too - as we are moving rapidly towards an aviation period of far less experience of this 'macho' flying that we have had since the Wright Brothers.
Talking Swiss cheeses, I am not aware of having loads of 'above G/S' ILS intercepts at GVA - a few, maybe in probably over 100 approaches. Maybe I just had the energy levels sorted out?
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Ever been to GVA with your VIPs? And in what aircraft? Intercept from above is the norm.
Anyway I already made a mention on the difference between approaching from above before or after the FAP. If the aircraft was cleared down to 2,000' it shouldn't have been lower after overshooting the GS and I doubt your SOPs would be fine with it.
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"If"?
If your aunt had wheels then she would be a tea cart. It is simple, really.
Hey Guys, how about waiting for the report before telling us at length exactly what we need to know about this particular accident? Without that report there are too many unanswered questions about what led up to the accident so that we need to see the radio transmissions, the CVR exchanges, the power settings, etcetera, with all of these on a time-line... after we have seen all of that stuff then we might be able to understand far better what went on there at Schiphol.
Without a report how, for instance, should we have understood what happened with that Colgan Dash 8? Initially that was another "simple" one: "Got too slow in heavy icing, stalled it, went in from a low altitude" seemed to be the initial consensus from what I remember. Well, it turns out that one was simple in terms of "what" but completely baffling in terms of "why," absolutely not in line with reasonable guesses about the cause of the crash.
Here again, we have much of the "what" but perhaps not enough to make a good guess at the "why" so that I think waiting for that report might be a good idea.
What we as individuals think about doing a GS intercept from above (when opinions here range from "It is all in a day's work," or "It happens more often than you might think," to "Are you mad?!") is of little import and much less interest than what the Dutch and Turkish authorities will say about that in this report.
Hey Guys, how about waiting for the report before telling us at length exactly what we need to know about this particular accident? Without that report there are too many unanswered questions about what led up to the accident so that we need to see the radio transmissions, the CVR exchanges, the power settings, etcetera, with all of these on a time-line... after we have seen all of that stuff then we might be able to understand far better what went on there at Schiphol.
Without a report how, for instance, should we have understood what happened with that Colgan Dash 8? Initially that was another "simple" one: "Got too slow in heavy icing, stalled it, went in from a low altitude" seemed to be the initial consensus from what I remember. Well, it turns out that one was simple in terms of "what" but completely baffling in terms of "why," absolutely not in line with reasonable guesses about the cause of the crash.
Here again, we have much of the "what" but perhaps not enough to make a good guess at the "why" so that I think waiting for that report might be a good idea.
What we as individuals think about doing a GS intercept from above (when opinions here range from "It is all in a day's work," or "It happens more often than you might think," to "Are you mad?!") is of little import and much less interest than what the Dutch and Turkish authorities will say about that in this report.
Blame
lederhosen, et al, why not attribute blame.
We may have different understandings of blame. Blame implies to find fault, to censure, a condemnation, and being responsible for a fault or error; thus culpability.
The alternative is the contributors to an accident; items which either pre-existed or were active failures and came together in the event. I would agree that the crew may have contributed to the accident.
In both cases I avoid cause as most accidents have more than one cause, although in this instance there may be a unique trigger to the final events.
A problem with blame is that it can inhibit understanding which is required to learn lessons and improve safety, because there is no need to look beyond blame. Blame is an easy route to closing down an investigation, it provides opportunity to move on, but without fully understanding the effect of the contributions and thus the issues likely to prevent other, similar events.
Paired with blame is hindsight bias; errors or omissions are easy to see in hindsight and thus support blame.
In agreeing that the crew contributed to the accident, I take care not to define the degree (the effect or proportion) of their contribution. Also, many aspects of the crews behaviour might be understandable when considering organisational aspects items which affect and shape crew behaviour the crews contribution.
This can be represented by an accident model which has both a person and an organisation channel into the accident. In the flow of events, it is relatively easy for an organisational aspect to reduce peoples capabilities (changing channels) tight / fast ATC vectoring. However, the person, at this relatively late stage, may not be able to affect the organisational aspect (difficult to change channels) saying no to ATM, or to fly a GA (peer pressure in a stream of traffic).
Most of the examples of airmanship (#2662), are statements or assumptions without qualification no reasons why, i.e what supports the conclusion, why should we think this way, why didnt the accident crew think similarly?
Many posts make the assumption that the crew identified (saw and understood) the malfunction in a reasonable timescale and therefore could have flown a GA at a safe height, but if the crew didnt see and understand immediately, as indicated by the Captains late actions, we have to consider why the malfunction could have been overlooked.
We must see the situation as the crew might have done at the time, we should consider what their thoughts might have been, pressures, workload, and evaluate the reasons for their supposed action / inaction.
I suggest that the experienced professionals in this forum are qualified to consider these points, and particularly so if given the same resources as the investigators (e.g. CVR). The process is similar to debriefing what happened, when, why, - oh I didnt see it, it wasnt how I interpreted that, or I didnt think of it, etc, etc, - all lessons learnt / to be learnt.
The combined wisdom in this forum might provide a very accurate (plausible) sequence of events based on their experiences in similar situations recalling what has been learned in other operations, and relating these to this event.
The debate could identify the most likely contributions to the accident, yet avoiding the degree of their contribution as without additional information this tends to be biased by individuals opinions.
Organisational issues are often dominant contributors to accidents; not withstanding the oft quoted 75% human contribution, which can be offset by organisation/system issues enabling error. Organisational issues may be easier to identify and fix, and the fixes are probably more reliable and cost-effective than attempting to change human behaviour.
However, I dont exclude issues of human behaviour and the need for the highest levels of professionalism / airmanship in our industry, but that need does not come from blame, and indeed blame would not necessary improve professionalism.
We may have different understandings of blame. Blame implies to find fault, to censure, a condemnation, and being responsible for a fault or error; thus culpability.
The alternative is the contributors to an accident; items which either pre-existed or were active failures and came together in the event. I would agree that the crew may have contributed to the accident.
In both cases I avoid cause as most accidents have more than one cause, although in this instance there may be a unique trigger to the final events.
A problem with blame is that it can inhibit understanding which is required to learn lessons and improve safety, because there is no need to look beyond blame. Blame is an easy route to closing down an investigation, it provides opportunity to move on, but without fully understanding the effect of the contributions and thus the issues likely to prevent other, similar events.
Paired with blame is hindsight bias; errors or omissions are easy to see in hindsight and thus support blame.
In agreeing that the crew contributed to the accident, I take care not to define the degree (the effect or proportion) of their contribution. Also, many aspects of the crews behaviour might be understandable when considering organisational aspects items which affect and shape crew behaviour the crews contribution.
This can be represented by an accident model which has both a person and an organisation channel into the accident. In the flow of events, it is relatively easy for an organisational aspect to reduce peoples capabilities (changing channels) tight / fast ATC vectoring. However, the person, at this relatively late stage, may not be able to affect the organisational aspect (difficult to change channels) saying no to ATM, or to fly a GA (peer pressure in a stream of traffic).
Most of the examples of airmanship (#2662), are statements or assumptions without qualification no reasons why, i.e what supports the conclusion, why should we think this way, why didnt the accident crew think similarly?
Many posts make the assumption that the crew identified (saw and understood) the malfunction in a reasonable timescale and therefore could have flown a GA at a safe height, but if the crew didnt see and understand immediately, as indicated by the Captains late actions, we have to consider why the malfunction could have been overlooked.
We must see the situation as the crew might have done at the time, we should consider what their thoughts might have been, pressures, workload, and evaluate the reasons for their supposed action / inaction.
I suggest that the experienced professionals in this forum are qualified to consider these points, and particularly so if given the same resources as the investigators (e.g. CVR). The process is similar to debriefing what happened, when, why, - oh I didnt see it, it wasnt how I interpreted that, or I didnt think of it, etc, etc, - all lessons learnt / to be learnt.
The combined wisdom in this forum might provide a very accurate (plausible) sequence of events based on their experiences in similar situations recalling what has been learned in other operations, and relating these to this event.
The debate could identify the most likely contributions to the accident, yet avoiding the degree of their contribution as without additional information this tends to be biased by individuals opinions.
Organisational issues are often dominant contributors to accidents; not withstanding the oft quoted 75% human contribution, which can be offset by organisation/system issues enabling error. Organisational issues may be easier to identify and fix, and the fixes are probably more reliable and cost-effective than attempting to change human behaviour.
However, I dont exclude issues of human behaviour and the need for the highest levels of professionalism / airmanship in our industry, but that need does not come from blame, and indeed blame would not necessary improve professionalism.
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chuks: "Hey Guys, how about waiting for the report" . . .
. . . Wait 2 years before anyone should theorize about the probable cause of why a B738 would stall and fall out of the sky in broad daylight, on short final approach at a busy airport in a large metropolitan area?
. . . Wait 2 years before anyone should theorize about the probable cause of why a B738 would stall and fall out of the sky in broad daylight, on short final approach at a busy airport in a large metropolitan area?
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Yup!
Check out the AF447 thread! Very few facts, just pages and pages of wild speculation, all done in the name of finding an answer to the burning question of what happened, without enough facts to work with do that.
Here we have been told that the report should be out fairly soon so that waiting a bit seems like the way to go, to me anyway.
The event itself doesn't seem to present much of a puzzle given the basic facts we (think we) know. The stuff we need to understand the event better is going to be in that report, such as the exact ATC clearance given, how events were understood and reacted to by the crew as shown by the FDR and CVR, etcetera.
I am sure that we all have our personal opinions about this accident and you could plot them along a line from no blame attached to the crew to all the blame attached to the crew, when the (arguable and relative) truth must be somewhere along that line but not at either end. That isn't what matters from the point of view of improving safety, though. For that we need to identify the causes of the accident so that we need the report itself.
Almost all of us know to relax back pressure when the stick shaker actuates or to put in TOGA power when the airspeed is sagging. We don't need to bloviate at length here to show that, really. What we don't know is simply why these accident crewmen missed what "everyone else knows."
It is like the debrief from a sim session where we made some surprising mistake, one we weren't even aware of until told about it. Yup, there it is on the print-out and the video recording, us shutting off the wrong generator, say. The only question remaining of any value then is, "Why?"
It isn't as though one always is told "You made a clumsy mistake. No one should make such a clumsy mistake." No, it is "You made a clumsy mistake because..." Here it is that "because" that we are looking for, not as much fun as pointing a finger and pontificating about the finer points of flying.
Here we have been told that the report should be out fairly soon so that waiting a bit seems like the way to go, to me anyway.
The event itself doesn't seem to present much of a puzzle given the basic facts we (think we) know. The stuff we need to understand the event better is going to be in that report, such as the exact ATC clearance given, how events were understood and reacted to by the crew as shown by the FDR and CVR, etcetera.
I am sure that we all have our personal opinions about this accident and you could plot them along a line from no blame attached to the crew to all the blame attached to the crew, when the (arguable and relative) truth must be somewhere along that line but not at either end. That isn't what matters from the point of view of improving safety, though. For that we need to identify the causes of the accident so that we need the report itself.
Almost all of us know to relax back pressure when the stick shaker actuates or to put in TOGA power when the airspeed is sagging. We don't need to bloviate at length here to show that, really. What we don't know is simply why these accident crewmen missed what "everyone else knows."
It is like the debrief from a sim session where we made some surprising mistake, one we weren't even aware of until told about it. Yup, there it is on the print-out and the video recording, us shutting off the wrong generator, say. The only question remaining of any value then is, "Why?"
It isn't as though one always is told "You made a clumsy mistake. No one should make such a clumsy mistake." No, it is "You made a clumsy mistake because..." Here it is that "because" that we are looking for, not as much fun as pointing a finger and pontificating about the finer points of flying.
Last edited by chuks; 5th Feb 2010 at 06:48.
PEI mate you are turning this into a doctoral dissertation. I respond because you highlight my name in capitals. Despite what PJ2 says I interpret what you say as disagreement with my view that there are already important lessons to be learned.
This is a professional pilots forum. Most of what you have written is semantics and will go right over the head of most of us simple pilots, particularly the non level 6 english ones.
Apparently you are retired, so this is an intellectual exercise for you and it is not terribly relevant how long the final report takes. For those of us still flying, and training new pilots to fly the 737, there are already some pretty clear facts about this sad accident. One of the main benefits of this forum is sharing this kind of information.
Most issues have been covered in detail in previous posts. I would highlight again that this accident demonstrates why being stabilised at 1000 feet in IMC is a good idea. It is irrelevant whether they recognised the nature of the failure. Any number of other things could and indeed might have occured. The reason for this gate is to give some margin so that a go-around does not become an accident as in this case.
It is a fact that if they had started the go-around earlier they would have been less likely to crash. The speed would obviously have been higher, and there would have had more height to recover.
Overdependence on automatics is also an important topic.
It is a fact that if the pilot had been flying manually the autothrottle problem would have been irrelevant. For the non 737 pilots it is a big no no to leave the autothrottle engaged while flying manually.
No harm is done by being reminded of these points.
Most of us would love to live in a world where the only words in the operations manual were 'DO NOT CRASH'. Of course there are bigger issues. But most of us have little influence over the organisational culture of Turkish Airlines et al. Those of us flying can try to learn from the obvious errors that did occur, irrespective of who was to blame.
I respect PEI's obvious knowledge and experience. Actually I do not think there is much difference between his and my views, or those of many others such as PJ2.
This is a professional pilots forum. Most of what you have written is semantics and will go right over the head of most of us simple pilots, particularly the non level 6 english ones.
Apparently you are retired, so this is an intellectual exercise for you and it is not terribly relevant how long the final report takes. For those of us still flying, and training new pilots to fly the 737, there are already some pretty clear facts about this sad accident. One of the main benefits of this forum is sharing this kind of information.
Most issues have been covered in detail in previous posts. I would highlight again that this accident demonstrates why being stabilised at 1000 feet in IMC is a good idea. It is irrelevant whether they recognised the nature of the failure. Any number of other things could and indeed might have occured. The reason for this gate is to give some margin so that a go-around does not become an accident as in this case.
It is a fact that if they had started the go-around earlier they would have been less likely to crash. The speed would obviously have been higher, and there would have had more height to recover.
Overdependence on automatics is also an important topic.
It is a fact that if the pilot had been flying manually the autothrottle problem would have been irrelevant. For the non 737 pilots it is a big no no to leave the autothrottle engaged while flying manually.
No harm is done by being reminded of these points.
Most of us would love to live in a world where the only words in the operations manual were 'DO NOT CRASH'. Of course there are bigger issues. But most of us have little influence over the organisational culture of Turkish Airlines et al. Those of us flying can try to learn from the obvious errors that did occur, irrespective of who was to blame.
I respect PEI's obvious knowledge and experience. Actually I do not think there is much difference between his and my views, or those of many others such as PJ2.
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Autopilot Pitch Trim
Should pitch trim be allowed to continue to run nose up when below bug speed, just to stay on the glideslope?
Sure, the THY crew had stall protection in the form of shaker; that's a bit late when close to the ground. Seems like most here agree the excessive pitch trim caused excessive pitch up when full power applied.
Would the crew have been better served in this energy decay for the autopilot to not trade airspeed for glideslope? If the autopilot had bug speed priority over glideslope, the GPWS would have provided adequate warning of Glideslope deviation, while the plane still had safe airspeed and trim. At the same time, it would be preserving energy to maximize the glide.
GB
Sure, the THY crew had stall protection in the form of shaker; that's a bit late when close to the ground. Seems like most here agree the excessive pitch trim caused excessive pitch up when full power applied.
Would the crew have been better served in this energy decay for the autopilot to not trade airspeed for glideslope? If the autopilot had bug speed priority over glideslope, the GPWS would have provided adequate warning of Glideslope deviation, while the plane still had safe airspeed and trim. At the same time, it would be preserving energy to maximize the glide.
GB
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If the autopilot had bug speed priority over glideslope, the GPWS would have provided adequate warning of Glideslope deviation, while the plane still had safe airspeed and trim. At the same time, it would be preserving energy to maximize the glide.
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Isn't it so that the elevator trim simply runs to unload the pitch actuator? The autopilot "tells" the actuator to exert some force and then the trim runs to zero the force, so that it's not a highly intelligent system.
Once you drop to an arbitrary bug speed do you really want to depart the glideslope in the direction of terra firma to depend on the GPWS or EGPWS? If you bugged a too-high speed that could have really unwanted consequences so that I think it might be better to stick with what we have, the autopilot chasing that sometimes elusive glideslope and the autothrottle or the Pilot Flying sorting out the more-stable speed. You can fly off the glideslope a lot quicker than you can change the speed, in other words. Too, once you have the glideslope at full scale, when that won't take very long, especially close-in, that mandates a go-around. The same sort of incapability that might let speed drop might also lead to an attempt to recover the glideslope despite what the rules say.
Once you drop to an arbitrary bug speed do you really want to depart the glideslope in the direction of terra firma to depend on the GPWS or EGPWS? If you bugged a too-high speed that could have really unwanted consequences so that I think it might be better to stick with what we have, the autopilot chasing that sometimes elusive glideslope and the autothrottle or the Pilot Flying sorting out the more-stable speed. You can fly off the glideslope a lot quicker than you can change the speed, in other words. Too, once you have the glideslope at full scale, when that won't take very long, especially close-in, that mandates a go-around. The same sort of incapability that might let speed drop might also lead to an attempt to recover the glideslope despite what the rules say.
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In another time, there were not bugs. Further, one needed a sense of Pitch and altitude. Have we sacrificed too much pilotage on the altar of gadgets? If there is a bug, and not looking at it can bring down an airliner full of actual people, where have the you know, actual pilots gone?
bear
bear
When teaching stalling in the simulator on a type rating course, this was normally a hand-flown exercise. The briefing would normally be that use of elevator trim down to Vfto (for example) with a clean wing was permitted but below that speed, the candidate was expected to keep back pressure on the control column down to the stick shaker whilst maintaining altitude when a recovery was made. In this case, only about 200 -300 feet would be lost.
This continued through various wing configurations right down to the point where the gear was down and land flap was set flying level with 30 degrees of bank set. Elevator trim was allowed down to Vref and then height was maintained with average approach power set using back pressure on the control column and this time we went right through the stick shaker to stick push when a recovery was made. In this case around 700 - 800 feet would be lost.
Some years later, we got to thinking about what might happen if we got to the stick shaker with the autopilot engaged. Imagine the scenario; lousy weather, crew tired, lots of problems, heavy ATC and we get to the bottom of descent and either the auto throttles don't work or we forget to advance the throttles.
In this case, the aircraft levels off and the automatics keep trimming back until the stick shaker activates and the autopilot falls out. In this case, the PF takes control pretty quickly and applies a large handful of power and then suddenly discovers that the elevator trim is somewhere near the aft limit.
If you don't push like hell and get the elevator trim moving forward in an expeditious fashion, the rest of the flight might just be a bit shorter and a bit more interesting than you had ever planned on!
This continued through various wing configurations right down to the point where the gear was down and land flap was set flying level with 30 degrees of bank set. Elevator trim was allowed down to Vref and then height was maintained with average approach power set using back pressure on the control column and this time we went right through the stick shaker to stick push when a recovery was made. In this case around 700 - 800 feet would be lost.
Some years later, we got to thinking about what might happen if we got to the stick shaker with the autopilot engaged. Imagine the scenario; lousy weather, crew tired, lots of problems, heavy ATC and we get to the bottom of descent and either the auto throttles don't work or we forget to advance the throttles.
In this case, the aircraft levels off and the automatics keep trimming back until the stick shaker activates and the autopilot falls out. In this case, the PF takes control pretty quickly and applies a large handful of power and then suddenly discovers that the elevator trim is somewhere near the aft limit.
If you don't push like hell and get the elevator trim moving forward in an expeditious fashion, the rest of the flight might just be a bit shorter and a bit more interesting than you had ever planned on!