AS332L2 Ditching off Shetland: 23rd August 2013
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Okay thanks. And do we know if the accident aircraft was "fully coupled" into this arrangement (and executing what might be considered a normal approach) before things started changing?
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GF
No, it was not fully coupled.
You may wish to have another look at the AAIB report and the posts on this thread since then.
You may wish to have another look at the AAIB report and the posts on this thread since then.
Last edited by Ray Joe Czech; 6th Sep 2013 at 11:22.
Metcha, the sensors used are common to the screens and the autopilot. Pitch, roll, heading, slip and vertical speed all come from the two AHRS - normally configured so that AHRS 1 is displayed on the LH set of screens, AHRS2 on the right. They are constantly cross checked at various points and any discrepancies between them are flagged up by the appropriate screen zones going amber.
However, the autopilot is very clever and doesn't just blindly use the pitch, roll, HDG etc data. It looks at the raw pitch rate, roll rate, yaw rate and tri axial accelerating coming direct from the AHRSs fibre optic gyros and accelerometers and calculates its own values of pitch, roll and heading and vertical speed. Long term, it will "like" one of the two AHRS and slowly wash out any integration errors so that it values merge. However, if an AHRS throws a wobbly, it will ignore it and just look at the other one (and the standby AHRS) quite seamlessly.
Air data similarly is used by both the screens and the autopilot, LH Sensor for LH pilot etc. the autopilot will in general use the air data from the pilot flying's side unless it fails or is unreasonable, in which case it will seamlessly use the other side. Again, there is cross checking between the two air data sensors at several levels, and the any discrepancies are made very visible to the pilots.
Nav data is a little more simplistic - the selected Nav data is displayed by the screen and used by the autopilot according to which screen is coupled. But of course there is automatic cross checking and any discrepancy between say ILS 1 and ILS 2 is flagged up. The autopilot is very clever in its use of Nav data - it hybridises it with inertial data so that, for example with a brief loss of ILS signal, the flight path is unaffected.
There is a degree of hybridisation of the air data too, but since there isn't necessarily a direct correlation between air data (say airspeed) and inertial data (ie ground speed), due to gusts for example, the inertial component is not that great. Of course its greater for altitude data since sudden pressure changes don't happen in the way that sudden wind changes do.
Phew, a bit complicated as you can see, and its all very clever! The bottom line for the pilots though, is that it just works, and works very precisely and intuitively.
However, the autopilot is very clever and doesn't just blindly use the pitch, roll, HDG etc data. It looks at the raw pitch rate, roll rate, yaw rate and tri axial accelerating coming direct from the AHRSs fibre optic gyros and accelerometers and calculates its own values of pitch, roll and heading and vertical speed. Long term, it will "like" one of the two AHRS and slowly wash out any integration errors so that it values merge. However, if an AHRS throws a wobbly, it will ignore it and just look at the other one (and the standby AHRS) quite seamlessly.
Air data similarly is used by both the screens and the autopilot, LH Sensor for LH pilot etc. the autopilot will in general use the air data from the pilot flying's side unless it fails or is unreasonable, in which case it will seamlessly use the other side. Again, there is cross checking between the two air data sensors at several levels, and the any discrepancies are made very visible to the pilots.
Nav data is a little more simplistic - the selected Nav data is displayed by the screen and used by the autopilot according to which screen is coupled. But of course there is automatic cross checking and any discrepancy between say ILS 1 and ILS 2 is flagged up. The autopilot is very clever in its use of Nav data - it hybridises it with inertial data so that, for example with a brief loss of ILS signal, the flight path is unaffected.
There is a degree of hybridisation of the air data too, but since there isn't necessarily a direct correlation between air data (say airspeed) and inertial data (ie ground speed), due to gusts for example, the inertial component is not that great. Of course its greater for altitude data since sudden pressure changes don't happen in the way that sudden wind changes do.
Phew, a bit complicated as you can see, and its all very clever! The bottom line for the pilots though, is that it just works, and works very precisely and intuitively.
Yes, inadequate training but also SOPs in the use of automation may be lacking, though these an operator and even fleet specific thing.
II not really, the HFDM can only check compliance with the SOPs as they stand, and only in terms of the flight path and not the briefing, CRM etc.
It will only detect a "near miss" if the flight path deviates from normal, and before this event, most of us would have said that an NPA was a pretty straightforward thing and not prone to "near misses". But the point of good SOPs, CRM etc is not to make most of the approaches good ones, that happens naturally, but to cater for the very rare times when all the holes in the cheese line up.
Anyway, I would say CHC have the best HFDM system of the bunch, although HFDM on the L2 is difficult due to some daft design decisions by EC as to what is recorded.
It will only detect a "near miss" if the flight path deviates from normal, and before this event, most of us would have said that an NPA was a pretty straightforward thing and not prone to "near misses". But the point of good SOPs, CRM etc is not to make most of the approaches good ones, that happens naturally, but to cater for the very rare times when all the holes in the cheese line up.
Anyway, I would say CHC have the best HFDM system of the bunch, although HFDM on the L2 is difficult due to some daft design decisions by EC as to what is recorded.
Last edited by HeliComparator; 6th Sep 2013 at 11:49.
HC, 
Thank you for your detailed but easily understood description of the sensor and autopilot system. It makes sense to me, and I can also now see why a sensor failure is unlikely to be a significant factor in this accident.
Thank you for your detailed but easily understood description of the sensor and autopilot system. It makes sense to me, and I can also now see why a sensor failure is unlikely to be a significant factor in this accident.
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OK, I've been lurking on this thread since it started, and I want to pose some possibly controversial thoughts and questions that may or may not take it back to the "shields down" stage that was mentioned a long number of posts ago.
I need to be up front here and say before I start that I have zero experience at the sharp end of rotary wing, and not much rotary SLF either, but I do have relevant FW professional level licensing, and spent a lot of time working very closely with simulator work, and related areas, including development work with FW MCC when it came into increased focus after Kegworth, as well as some very academic level research work with a major FW manufacturer, which was an eye opener at times, the protectionism even between partners in projects was at times verging on paranoid, but there were probably good reasons for it, given some of the things that have come out of the woodwork since that time.
So, here we go, and I don't have an agenda here against the people at the sharp end, but I do have some issues with the mentality and validity that is behind some of the decision making that's gone on at higher levels.
First, some possibly loaded questions, and the reason will I hope become apparent further down.
If a pilot expresses an interest in learning more about the extremes of the envelope for the type that he (she also assumed for political correctness, ) is flying, and wants to do some extra sim time, is that encouraged or frowned on by the fleet captains, instructors, etc, or facilitated as being "a good idea", or is that pilot black marked for possibly having a handling problem that they don't want to admit to?
Are the simulator instructors people with long experience on the type, or people with a type rating who have been rostered in to sim work for a while?
Is there any "spare" time in the mandatory simulator sessions to allow for "envelope exploring", where a specific scenario can be explored, or analysed, or is sim time so specific that there is only time for the "mandatory" stuff that is deemed essential to pass the check ride and maintain legal currency?
Is maintenance in house, or contracted out to external providers? regardless of where the service is provided, does that service have any "spare capacity" that allows them to cover in a timely manner squawks that are reported but not critical to continued operations?
Is there any slack in airframe usage scheduling to allow for unplanned maintenance, or do non critical squawks get deferred to the next scheduled check date/time?
Does the company have any formal procedure for raising issues with SOP's that don't produce the required result, or for reviewing SOP's that produced an ambiguous result in certain circumstances?
Are there any "local exceptions" to SOP's that everyone knows about, and uses, but are not part of the documented operation?
I am going to digress a little here, and this is unfortunately fixed wing rather than rotary, but it was specific, and may explain where some of my thoughts are coming from.
A long time ago, at a flight simulation conference on the other side of the pond, visits to local sim providers were part of the agenda. One of those visits was to a small GA jet aircraft simulator, and the 2 of us that were in that session (licensed pilots, but not type rated, and with varying experience) were introduced to an exercise that was not "standard training", but was used for fun but with a few fringe benefits. The exercise was to start from "a sea level runway threshold", in CAVOK conditions, ready to roll. As brakes were released, start the stop watch. Take off, climb to 10,000 Ft, then land back, any runway, and stop, at brakes on, the stop watch stops, shortest time wins, only rule is don't break the airframe.
It was an interesting session, and went on over time to become an interesting challenge when taken back to various places with other simulators. In theory a bit of fun, but what it highlighted very positively was the need to have raw data handling and flying skills, and to be able to fly to the extremes of the envelope in order to get the best time, with looking out of the window to assess the progress an essential part of the exercise.
Where it became thought provoking was when the same scenario was moved the other end of the spectrum, a 747-400 simulator, and tried in some spare time on type rated first officers. The same 2 non type rated people that had first been introduced to this exercise had successfully both set a time of about 6 minutes 30 seconds. When 3 different type rated crew members tried the same scenario, 2 of the 3 broke the airframe in the air, and it was clear that the reason was unfortunately that they were so used to flying the magenta line, and staying within the 10% of the envelope either side of straight and level, when it came to doing things at the edge of the envelope, they had never been anywhere even close to it. and to make it worse, did not have the underlying raw data and "look out of the window" flying skills to allow them to do something very different from flying it with everything on and working correctly
As part of a multi disciplinary EU wide research project with one of the major aircraft manufacturers human factors section, we did some serious work with a "generic" airbus, and as part of the research, we had to do a number of exercises in a level D simulator, to validate what "our" simulator was going to do. We "discovered" that one major european airline had not required their simulator provider to handle some of the more extreme ends of the envelope in respect to manual reversion, as "the analysts" (for analysts read beancounters) had decided that the statistical chance of this event happening on an airframe was/is so low, the costs of implementing that level of reality in the simulator, and training how to manage it "are not justified". We ended up having to go across to the West Coast of the USA to a different manufacturer's simulator, in a different carrier, in order to get the results we needed, as they had implemented the needed code to provide training, and were doing so. These 2 examples were not with Low cost carriers, and they happened 10 years ago before the recent recession and increased pressures on margins.
For me, the holes in the swiss cheese are several.
The reduction in the numbers of ex military pilots coming into civilian aviation, (FW and rotary) they have had to be replaced somehow, and there is unfortunately no short cut to experience.
The reluctance of bean counters to respect and retain the high hours experienced pilots, because they are worth paying a premium for.
The downgrading of the skill levels of the instructors in simulators, they now "tick boxes" to show that the exercise has been done, rather than ensure that the subtle "gotchas" have been discovered and learnt, and in some cases, they never learnt the gotchas themselves, because "The system" no longer allows for flexibility in the sim, it only covers the basics, and recurrency.
The reduction in the number and skill levels of maintenance, partly through bean counter pressure, and partly through regulatory "allowance" mean that there is not the "slack" in the system to allow for non scheduled events in the way there used to be, and the reduced numbers of licensed and type rated engineers spend a higher proportion of their time signing and rubber stamping the paperwork to protect the posteriors of the higher echelons of management in the event of a failure, mistake or problem..
The increase in pressure to use automation on all occasions ("To reduce costs") has diluted the skill base in subtle and insidious ways, resulting in an increase in airframe operators rather than drivers, the difference being that drivers are ahead of the automation, operators are with or behind the automation
The increase in allowed duty time, and related issues around things like travel, means that there are subtle increases in fatigue levels, so reacting and responding in a timely manner to insidious events before they become incidents or accidents is potentially more problematic
A close friend of mine was much involved with the design and implementation of the first FW CAT 3 autoland on Trident, and he shares some of the concerns that I've outlined above, and has (with me) only contempt for the scenario where an underskilled crew stayed stalled all the way down to a fatal accident because they lacked the raw data flying skills to recognise and adequately deal with an unreliable airspeed. Some of the other recent FW incidents are equally reprehensible, to the extent that San Francisco has, as a result of the Asiana accident, "banned hand flown approaches" to the 2 runways that approach over water for foreign aircrews. What an indictment of standards!
In the recent and under discussion incident that is the subject of this thread, it is reasonably clear from the comments and suggestions that the airframe has now been deemed to be failure free, but can we really call the now impied and underlying cause "pilot error", or should be more realistically be calling this, and many other incidents and accidents in both FW and rotary flying "system errors", in that while the pilots may well have been the first to arrive at the scene of the accident, it may not have been a failing on their part alone that contributed or caused that arrival to happen in the first place. That for me is what is screaming out loud in this very thought provoking thread, and what needs to be addressed by the oil companies, the operators, the airframe manufacturers, the regulators and the passengers, as it is only when all of these groups are working together that some of these issues will be adequately and effectively addressed.
The last comment, which may or may not be relevant, in among all the statistics about flying hours, and types and accident ratios, has anyone factored in the passenger kilometers, from what I have seen of it, the number of passenger kilometers flown is significantly higher in the NS than in other areas, so the number of fatalities per passenger kilometer will probably end up being lower than places like the GOM.
I'm not saying that the NS operators can be complacent as a result of that, far from it, the stakes are so much higher with larger airframes.
If I've ruffled feathers, I hope I've done in in a constructive way, based on observations and feedback from what I regard as reliable sources, and an unemotional overview of a very long thread.
I have no malice or hidden agenda towards the people that are at the sharp end, far from it, if I have a target, it would be the faceless bean counters at all levels of the oil companies, operators and regulators that make decisions that are unrelated to the wider picture that is the reality of day to day operations in what I recognise is sometimes a very hostile environment.
The people at the sharp end do what they do, in the way that they do it, because "the system" says that is the way they should work, and rarely do they deviate from those ways. I hope that my comments here cause people to stop and think about "the system" in a wider and unemotional way, and if "the system" seems to be faulty, for whatever reason, it is time to find a way to speak out and say so, rather than hoping that someone else will speak out .
I need to be up front here and say before I start that I have zero experience at the sharp end of rotary wing, and not much rotary SLF either, but I do have relevant FW professional level licensing, and spent a lot of time working very closely with simulator work, and related areas, including development work with FW MCC when it came into increased focus after Kegworth, as well as some very academic level research work with a major FW manufacturer, which was an eye opener at times, the protectionism even between partners in projects was at times verging on paranoid, but there were probably good reasons for it, given some of the things that have come out of the woodwork since that time.
So, here we go, and I don't have an agenda here against the people at the sharp end, but I do have some issues with the mentality and validity that is behind some of the decision making that's gone on at higher levels.
First, some possibly loaded questions, and the reason will I hope become apparent further down.
If a pilot expresses an interest in learning more about the extremes of the envelope for the type that he (she also assumed for political correctness, ) is flying, and wants to do some extra sim time, is that encouraged or frowned on by the fleet captains, instructors, etc, or facilitated as being "a good idea", or is that pilot black marked for possibly having a handling problem that they don't want to admit to?
Are the simulator instructors people with long experience on the type, or people with a type rating who have been rostered in to sim work for a while?
Is there any "spare" time in the mandatory simulator sessions to allow for "envelope exploring", where a specific scenario can be explored, or analysed, or is sim time so specific that there is only time for the "mandatory" stuff that is deemed essential to pass the check ride and maintain legal currency?
Is maintenance in house, or contracted out to external providers? regardless of where the service is provided, does that service have any "spare capacity" that allows them to cover in a timely manner squawks that are reported but not critical to continued operations?
Is there any slack in airframe usage scheduling to allow for unplanned maintenance, or do non critical squawks get deferred to the next scheduled check date/time?
Does the company have any formal procedure for raising issues with SOP's that don't produce the required result, or for reviewing SOP's that produced an ambiguous result in certain circumstances?
Are there any "local exceptions" to SOP's that everyone knows about, and uses, but are not part of the documented operation?
I am going to digress a little here, and this is unfortunately fixed wing rather than rotary, but it was specific, and may explain where some of my thoughts are coming from.
A long time ago, at a flight simulation conference on the other side of the pond, visits to local sim providers were part of the agenda. One of those visits was to a small GA jet aircraft simulator, and the 2 of us that were in that session (licensed pilots, but not type rated, and with varying experience) were introduced to an exercise that was not "standard training", but was used for fun but with a few fringe benefits. The exercise was to start from "a sea level runway threshold", in CAVOK conditions, ready to roll. As brakes were released, start the stop watch. Take off, climb to 10,000 Ft, then land back, any runway, and stop, at brakes on, the stop watch stops, shortest time wins, only rule is don't break the airframe.
It was an interesting session, and went on over time to become an interesting challenge when taken back to various places with other simulators. In theory a bit of fun, but what it highlighted very positively was the need to have raw data handling and flying skills, and to be able to fly to the extremes of the envelope in order to get the best time, with looking out of the window to assess the progress an essential part of the exercise.
Where it became thought provoking was when the same scenario was moved the other end of the spectrum, a 747-400 simulator, and tried in some spare time on type rated first officers. The same 2 non type rated people that had first been introduced to this exercise had successfully both set a time of about 6 minutes 30 seconds. When 3 different type rated crew members tried the same scenario, 2 of the 3 broke the airframe in the air, and it was clear that the reason was unfortunately that they were so used to flying the magenta line, and staying within the 10% of the envelope either side of straight and level, when it came to doing things at the edge of the envelope, they had never been anywhere even close to it. and to make it worse, did not have the underlying raw data and "look out of the window" flying skills to allow them to do something very different from flying it with everything on and working correctly
As part of a multi disciplinary EU wide research project with one of the major aircraft manufacturers human factors section, we did some serious work with a "generic" airbus, and as part of the research, we had to do a number of exercises in a level D simulator, to validate what "our" simulator was going to do. We "discovered" that one major european airline had not required their simulator provider to handle some of the more extreme ends of the envelope in respect to manual reversion, as "the analysts" (for analysts read beancounters) had decided that the statistical chance of this event happening on an airframe was/is so low, the costs of implementing that level of reality in the simulator, and training how to manage it "are not justified". We ended up having to go across to the West Coast of the USA to a different manufacturer's simulator, in a different carrier, in order to get the results we needed, as they had implemented the needed code to provide training, and were doing so. These 2 examples were not with Low cost carriers, and they happened 10 years ago before the recent recession and increased pressures on margins.
For me, the holes in the swiss cheese are several.
The reduction in the numbers of ex military pilots coming into civilian aviation, (FW and rotary) they have had to be replaced somehow, and there is unfortunately no short cut to experience.
The reluctance of bean counters to respect and retain the high hours experienced pilots, because they are worth paying a premium for.
The downgrading of the skill levels of the instructors in simulators, they now "tick boxes" to show that the exercise has been done, rather than ensure that the subtle "gotchas" have been discovered and learnt, and in some cases, they never learnt the gotchas themselves, because "The system" no longer allows for flexibility in the sim, it only covers the basics, and recurrency.
The reduction in the number and skill levels of maintenance, partly through bean counter pressure, and partly through regulatory "allowance" mean that there is not the "slack" in the system to allow for non scheduled events in the way there used to be, and the reduced numbers of licensed and type rated engineers spend a higher proportion of their time signing and rubber stamping the paperwork to protect the posteriors of the higher echelons of management in the event of a failure, mistake or problem..
The increase in pressure to use automation on all occasions ("To reduce costs") has diluted the skill base in subtle and insidious ways, resulting in an increase in airframe operators rather than drivers, the difference being that drivers are ahead of the automation, operators are with or behind the automation
The increase in allowed duty time, and related issues around things like travel, means that there are subtle increases in fatigue levels, so reacting and responding in a timely manner to insidious events before they become incidents or accidents is potentially more problematic
A close friend of mine was much involved with the design and implementation of the first FW CAT 3 autoland on Trident, and he shares some of the concerns that I've outlined above, and has (with me) only contempt for the scenario where an underskilled crew stayed stalled all the way down to a fatal accident because they lacked the raw data flying skills to recognise and adequately deal with an unreliable airspeed. Some of the other recent FW incidents are equally reprehensible, to the extent that San Francisco has, as a result of the Asiana accident, "banned hand flown approaches" to the 2 runways that approach over water for foreign aircrews. What an indictment of standards!
In the recent and under discussion incident that is the subject of this thread, it is reasonably clear from the comments and suggestions that the airframe has now been deemed to be failure free, but can we really call the now impied and underlying cause "pilot error", or should be more realistically be calling this, and many other incidents and accidents in both FW and rotary flying "system errors", in that while the pilots may well have been the first to arrive at the scene of the accident, it may not have been a failing on their part alone that contributed or caused that arrival to happen in the first place. That for me is what is screaming out loud in this very thought provoking thread, and what needs to be addressed by the oil companies, the operators, the airframe manufacturers, the regulators and the passengers, as it is only when all of these groups are working together that some of these issues will be adequately and effectively addressed.
The last comment, which may or may not be relevant, in among all the statistics about flying hours, and types and accident ratios, has anyone factored in the passenger kilometers, from what I have seen of it, the number of passenger kilometers flown is significantly higher in the NS than in other areas, so the number of fatalities per passenger kilometer will probably end up being lower than places like the GOM.
I'm not saying that the NS operators can be complacent as a result of that, far from it, the stakes are so much higher with larger airframes.
If I've ruffled feathers, I hope I've done in in a constructive way, based on observations and feedback from what I regard as reliable sources, and an unemotional overview of a very long thread.
I have no malice or hidden agenda towards the people that are at the sharp end, far from it, if I have a target, it would be the faceless bean counters at all levels of the oil companies, operators and regulators that make decisions that are unrelated to the wider picture that is the reality of day to day operations in what I recognise is sometimes a very hostile environment.
The people at the sharp end do what they do, in the way that they do it, because "the system" says that is the way they should work, and rarely do they deviate from those ways. I hope that my comments here cause people to stop and think about "the system" in a wider and unemotional way, and if "the system" seems to be faulty, for whatever reason, it is time to find a way to speak out and say so, rather than hoping that someone else will speak out .
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I think some of us are over-complicating the issue of understanding the difference between 3-axis and 4-axis modes. Whether the airspeed or descent angle is controlled by cyclic or collective input during an approach is not really important for most people, unless you are a pilot on the type or a technical nerd. What is important for most to understand is how the aircraft behaves using the different modes.
To compare with our fixed-wing colleagues:
If an airliner is flying an instrument approach using the autopilot to take care of the localizer and glide-angle and airspeed is controlled by the FP, then it is a "3-axis mode". Then in the fixed-wing the throttles must be manipulated by the FP, in a Super Puma it is the collective (power control).
If the auto-throttle is used on the same approach in our airliner, then it is similar to "4-axis", fully hands off.
To state that 3-axis approaches are inherently dangerous is over the top, there are thousands of airliners out there doing non-precision approaches every day with no A/T. Higher work-load? Yes, but with proper training, SOP's and good CRM the risk can be managed and controlled very well.
To compare with our fixed-wing colleagues:
If an airliner is flying an instrument approach using the autopilot to take care of the localizer and glide-angle and airspeed is controlled by the FP, then it is a "3-axis mode". Then in the fixed-wing the throttles must be manipulated by the FP, in a Super Puma it is the collective (power control).
If the auto-throttle is used on the same approach in our airliner, then it is similar to "4-axis", fully hands off.
To state that 3-axis approaches are inherently dangerous is over the top, there are thousands of airliners out there doing non-precision approaches every day with no A/T. Higher work-load? Yes, but with proper training, SOP's and good CRM the risk can be managed and controlled very well.
Last edited by Jimmy 16; 6th Sep 2013 at 12:58.
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AS:
Everything is possible, but I seriously doubt that this is the scenario here. Descent below MDA on a non-precision approach unless you have the runway or the approach light in sight is a big NO-NO.
If that had been a practice, it would have been picked up by my good friend using his HFDM system long ago.
Is it possible that the captain having seen a hole in the cloud, slowed down
and tried to descend while maintaining visual contact with the surface with the
intention of making the final run into LSI low level visual or something along
those lines?
and tried to descend while maintaining visual contact with the surface with the
intention of making the final run into LSI low level visual or something along
those lines?
If that had been a practice, it would have been picked up by my good friend using his HFDM system long ago.
Last edited by Jimmy 16; 6th Sep 2013 at 12:16.
Irish Steve, You certainly raise some thought provoking points, which I shall leave to people more qualified than me to comment upon.
With respect to:
It strikes me that both hours and distance flown are pretty crude measures for comparing accident statistics. Neither take account of differences in the pilot workload or the forces and fatigue to which the airframe and its systems are being subjected. Some measure of challenging to non-challenging flying really needs to be factored in to make a worthwhile comparison between operations in different parts of the world.
With respect to:
The last comment, which may or may not be relevant, in among all the statistics about flying hours, and types and accident ratios, has anyone factored in the passenger kilometers, from what I have seen of it, the number of passenger kilometers flown is significantly higher in the NS than in other areas, so the number of fatalities per passenger kilometer will probably end up being lower than places like the GOM.
Jimmy16 - surely the issue about which control does what in a mixed mode autopilot is exactly the key here.
Is it me or is the idea that the cyclic controlling RoD (VS) and the collective controlling IAS utterly counter-intuitive to everything that is taught in basic (and advanced) helicopter training?
Frankly if these guys ended up in a UP operating the aircraft in this configuration at a point of high workload (IMC looking for cloudbreak at minima), I for one am not surprised.
Is it me or is the idea that the cyclic controlling RoD (VS) and the collective controlling IAS utterly counter-intuitive to everything that is taught in basic (and advanced) helicopter training?
Frankly if these guys ended up in a UP operating the aircraft in this configuration at a point of high workload (IMC looking for cloudbreak at minima), I for one am not surprised.
Originally Posted by [email protected]
Is it me or is the idea that the cyclic controlling RoD (VS) and the collective controlling IAS utterly counter-intuitive to everything that is taught in basic (and advanced) helicopter training?
Frankly if these guys ended up in a UP operating the aircraft in this configuration at a point of high workload (IMC looking for cloudbreak at minima), I for one am not surprised.
Frankly if these guys ended up in a UP operating the aircraft in this configuration at a point of high workload (IMC looking for cloudbreak at minima), I for one am not surprised.
If you are flying in the cruise at MCP, and the aircraft starts to descend a bit, what do you teach? - raise the collective? Oh dear, now we've overtorqued! Oh well, just have to let it crash then.
If you pause to think about it, how you fly, and how you SHOULD be teaching, is that cyclic controls speed and collective controls altitude at low to medium speed, but at higher speeds you must control altitude with cyclic and that leaves collective for speed. Any other way just doesn't work. At high speed the cyclic has massive authority on vertical speed / altitude, the collective has minimal, or zero if you are already at the max. Fortunately this is understood by EC, who make the EC225 fly in just this way.
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Crab:
In a "mixed mode" (I don't like that term, 3-axis is easier) the collective is not part of the automatic game. The flying pilot must control the airspeed using the collective just like a fixed wing pilots uses his throttles to control airspeed. The autopilot is flying the aircraft laterally and vertically but not speed-wise.
In this 3-axis mode, all corrections in the vertical are done by the autopilot by changing the pitch angle of the aircraft. The pilot owns the collective.
I am sure that your SeaKing has something similar?
In a "mixed mode" (I don't like that term, 3-axis is easier) the collective is not part of the automatic game. The flying pilot must control the airspeed using the collective just like a fixed wing pilots uses his throttles to control airspeed. The autopilot is flying the aircraft laterally and vertically but not speed-wise.
In this 3-axis mode, all corrections in the vertical are done by the autopilot by changing the pitch angle of the aircraft. The pilot owns the collective.
I am sure that your SeaKing has something similar?
Last edited by Jimmy 16; 6th Sep 2013 at 12:54.
I sometimes poke a stick at HC....but always respect his views as he is quite experienced and intimately involved in introducing new Types to the North Sea Offshore flying business.
Most times that stick poking is done with the intent to get a response out of him....rarely does it fail.
My point about the "Monitoring" vs "Flying" comment was to bring a discussion on about the division of duties and tasks in the Cockpit.
My concern is Crews get complacent over time and might not be as "engaged" as is the AutoPilot. Some talk has been made about perhaps the Crew were distracted by something that allowed them to miss the Airspeed/Altitude/Power deviations that led to the aircraft striking the Sea in an uncontrolled manner.
My thought was to question just what it could be that would have that amount of attraction for BOTH pilots. In my old fashioned view, one of the Pilots was supposed to be flying the machine...which connotes using the Autopilot to do so. I also firmly believe that when I am the Pilot doing that....I keep a very close eye on the Autopilots performance and accuracy. Any deviation from what it should be doing is my responsibility. In every Two Pilot Crew Operation I flew in....the other Pilot was tasked to keep an eye on Me and the Aircraft amongst his many other duties that he did to relieve Me, the Flying Pilot, to carry out my Primary Task of flying the machine.
In normal operations or during a situation where an "Emergency" or Aircraft malfunction occurs, I as the "Flying" Pilot still had the Primary duty of flying the Aircraft and the Non-Flying Pilot was there to assist in dealing with whatelse was going on.
If I were the Captain/PIC...guy whose signature goes in the Tech Log....I made the Decisions with the other Pilots input and assistance....but I retained responsibility.
If for any reason, the other Pilot who was "Monitoring" my flying saw a problem or had a concern of any kind....he was obliged to speak up (however politely he had time for....) and point out the problem and hopefully announce what he thought needed to be done.
I also believe that if it is a dangerous situation developing due to some mistake or lapse I have had....the "Monitoring Pilot"....should either make the control input that is needed or take control of the aircraft away from the "Flying Pilot".
CRM teaches us that is the correct approach to situations where action needs to taken to keep the aircraft in a safe flight environment.
Thus....If we as a Crew allow ourselves to become less attentive than we should....and it would follow (in my view) that if the "Flying Pilot" is not as engaged as he should be....then the "Monitoring Pilot" is going to be that one step behind....or will often find himself in the position of having to make a decision to speak up or not and over time....his willingness and timeliness will be degraded by custom.
I get back to a question I asked early on in the Thread...."Why did the Crew, Two Well Trained, Qualified, Professional Pilots not realize what was going on and catch the loss of Airspeed and the resulting increase of ROD?" Just what occurred in that Cockpit that allowed this to happen?
I agree with many others....we should reserve "Pilot Error" for those situations where the Pilot(s) intentional violate SOP's, Procedures, Regulations and use the Term "Human Factors" to describe these kinds of tragedies where good Men make mistakes that are the result of many factors largely outside their control and doing.
Most times that stick poking is done with the intent to get a response out of him....rarely does it fail.
My point about the "Monitoring" vs "Flying" comment was to bring a discussion on about the division of duties and tasks in the Cockpit.
My concern is Crews get complacent over time and might not be as "engaged" as is the AutoPilot. Some talk has been made about perhaps the Crew were distracted by something that allowed them to miss the Airspeed/Altitude/Power deviations that led to the aircraft striking the Sea in an uncontrolled manner.
My thought was to question just what it could be that would have that amount of attraction for BOTH pilots. In my old fashioned view, one of the Pilots was supposed to be flying the machine...which connotes using the Autopilot to do so. I also firmly believe that when I am the Pilot doing that....I keep a very close eye on the Autopilots performance and accuracy. Any deviation from what it should be doing is my responsibility. In every Two Pilot Crew Operation I flew in....the other Pilot was tasked to keep an eye on Me and the Aircraft amongst his many other duties that he did to relieve Me, the Flying Pilot, to carry out my Primary Task of flying the machine.
In normal operations or during a situation where an "Emergency" or Aircraft malfunction occurs, I as the "Flying" Pilot still had the Primary duty of flying the Aircraft and the Non-Flying Pilot was there to assist in dealing with whatelse was going on.
If I were the Captain/PIC...guy whose signature goes in the Tech Log....I made the Decisions with the other Pilots input and assistance....but I retained responsibility.
If for any reason, the other Pilot who was "Monitoring" my flying saw a problem or had a concern of any kind....he was obliged to speak up (however politely he had time for....) and point out the problem and hopefully announce what he thought needed to be done.
I also believe that if it is a dangerous situation developing due to some mistake or lapse I have had....the "Monitoring Pilot"....should either make the control input that is needed or take control of the aircraft away from the "Flying Pilot".
CRM teaches us that is the correct approach to situations where action needs to taken to keep the aircraft in a safe flight environment.
Thus....If we as a Crew allow ourselves to become less attentive than we should....and it would follow (in my view) that if the "Flying Pilot" is not as engaged as he should be....then the "Monitoring Pilot" is going to be that one step behind....or will often find himself in the position of having to make a decision to speak up or not and over time....his willingness and timeliness will be degraded by custom.
I get back to a question I asked early on in the Thread...."Why did the Crew, Two Well Trained, Qualified, Professional Pilots not realize what was going on and catch the loss of Airspeed and the resulting increase of ROD?" Just what occurred in that Cockpit that allowed this to happen?
I agree with many others....we should reserve "Pilot Error" for those situations where the Pilot(s) intentional violate SOP's, Procedures, Regulations and use the Term "Human Factors" to describe these kinds of tragedies where good Men make mistakes that are the result of many factors largely outside their control and doing.
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In defence (but only a little 
) of Crab, this scenario is a low-medium speed regime, and it is a little bit (not utterly) counter-intuitive, at least initially, to control speed with collective and RoD with cyclic on an instrument approach.
However, it doesn't take much getting used to once you get your head round it, and our co-pilots seem to manage quite alright in a short time.
However, as the L2 flies apps quite happily fully coupled 95% of the time, there is rarely any need to do it 3-axis anyway.
) of Crab, this scenario is a low-medium speed regime, and it is a little bit (not utterly) counter-intuitive, at least initially, to control speed with collective and RoD with cyclic on an instrument approach.However, it doesn't take much getting used to once you get your head round it, and our co-pilots seem to manage quite alright in a short time.
However, as the L2 flies apps quite happily fully coupled 95% of the time, there is rarely any need to do it 3-axis anyway.
HC and, to a lesser extent, DB both come across, at least to me, as slightly patronizing; though I’m sure it’s unintentional. The fact remains that two of these all singing, all dancing machines ended up in the oggin.
On an average offshore flight, probably 90% of the flying is conducted fully coupled which means a 5,000 hour (experienced in offshore work only) pilot has around 500 hours manual flying under his belt. Narrow this down to manual flying where it counts – normally on the approach and landing – and you can reduce this figure considerably.
Now bring in, for example, the Air France and Asiana crashes where it was demonstratively obvious the crews lacked manual flying skills (now resulting in increasing concern among the FW world) and to me the whole indicate an erosion in manual handling skills coupled with a lack of understanding, or improper use of, the automated systems. To which of course, the disciples of automation will reply that more training is required in the use of the systems and those that express concerns should enter (or be dragged into) the 21st century.
And of course, they’re correct in this context.
But I’m puzzled as to why there is only a slight mention of manual skills; almost as though they’re taken for granted. I do feel there should more emphasis than shown on this thread placed on pure poling. Or is it that these skills are, in fact, not taken for granted and instead there’s a recognition that by virtue of today’s operations they are inevitably degraded and therefore we should concentrate on the technology available?
In any event, as one example, I think it would do no harm and probably a lot of good to include in the obligatory items in a visual OPC (and any other training session in the aircraft) a period of intense manual handling, particularly at night, without emergencies (other than the standard few minutes of AP out), coupled with a determination to counter the bean counter’s aversion to non-revenue flying.
On an average offshore flight, probably 90% of the flying is conducted fully coupled which means a 5,000 hour (experienced in offshore work only) pilot has around 500 hours manual flying under his belt. Narrow this down to manual flying where it counts – normally on the approach and landing – and you can reduce this figure considerably.
Now bring in, for example, the Air France and Asiana crashes where it was demonstratively obvious the crews lacked manual flying skills (now resulting in increasing concern among the FW world) and to me the whole indicate an erosion in manual handling skills coupled with a lack of understanding, or improper use of, the automated systems. To which of course, the disciples of automation will reply that more training is required in the use of the systems and those that express concerns should enter (or be dragged into) the 21st century.
And of course, they’re correct in this context.
But I’m puzzled as to why there is only a slight mention of manual skills; almost as though they’re taken for granted. I do feel there should more emphasis than shown on this thread placed on pure poling. Or is it that these skills are, in fact, not taken for granted and instead there’s a recognition that by virtue of today’s operations they are inevitably degraded and therefore we should concentrate on the technology available?
In any event, as one example, I think it would do no harm and probably a lot of good to include in the obligatory items in a visual OPC (and any other training session in the aircraft) a period of intense manual handling, particularly at night, without emergencies (other than the standard few minutes of AP out), coupled with a determination to counter the bean counter’s aversion to non-revenue flying.
HC
You have confused me now - surely an instrument approach is at low - medium speed yet it seems that the way pilots fly the approach is as if it were high speed.
Being a product of the RAF system I, like Crab was taught that cyclic controlled speed and that power via the collective controlled height. The scenario you put forward of cruising at max power didn't occur in most RAF operations as the helicopter was usually been aggresively flown at low level - 50ft in German Ex areas and 100ft elsewhere
HF
If you pause to think about it, how you fly, and how you SHOULD be teaching, is that cyclic controls speed and collective controls altitude at low to medium speed, but at higher speeds you must control altitude with cyclic and that leaves collective for speed.
Being a product of the RAF system I, like Crab was taught that cyclic controlled speed and that power via the collective controlled height. The scenario you put forward of cruising at max power didn't occur in most RAF operations as the helicopter was usually been aggresively flown at low level - 50ft in German Ex areas and 100ft elsewhere
HF
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I agree with many others....we should reserve "Pilot Error" for those situations where the Pilot(s) intentional violate SOP's, Procedures, Regulations and use the Term "Human Factors" to describe these kinds of tragedies where good Men make mistakes that are the result of many factors largely outside their control and doing.
Intentionally violating SOPs, procedures and/or regulations is not an "error", as the course of action followed was not unintended. That is where the word "negligent" starts to rear its ugly head.
"Human Factors" is very probably part of the chain that led to the Error being made, but to describe every mistake as simply Human Factors is, to me, too simplistic.