Mismanagement of automation
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Bravo -
"A quick dab on the FTR" (as you put it), - if the pilot is pushing significantly against the springs at the time (eg overcoming flapback during transition to forward flight ) will potentially result in a sudden nose-down jerk through the controls as they de-clutch. Clearly this could have serious negative consequences.
"A quick dab on the FTR" (as you put it), - if the pilot is pushing significantly against the springs at the time (eg overcoming flapback during transition to forward flight ) will potentially result in a sudden nose-down jerk through the controls as they de-clutch. Clearly this could have serious negative consequences.
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B73, 212
I agree but what happened happens. Only last week I sat in witness of it during a recurrent training session. The crew also operated a EC type and fell into their old habit.
You must be aware of those three certainties in aviation - the three laws...
1. Sod's Law - If it can happen then it will happen
2. Murphy's Law - If it's possible for someone to put something together the wrong way then they will.
3. The Jammy Toast Law - If you drop a piece of jammy toast then it will land jammy side down. (which, translated means if you trust to luck then don't be surprised if you are disappointed.)
I beg you to drag yourself away from your Eurocentric understanding of our world. My 394 students come from 52 different countries and whilst you may have a standard of competency equivalent to 'acceptable' most out there do not and only escape the need for more training courtesy of a world that uses a 'tick-box system in a'compliance' dominated world.
I would like to keep my boss happy by keeping pictures of wrecked AW139's off the front pages of the newspapers and to do that we need to keep those that are new to complex helicopters clear of areas that 'bite'.
What say you of the notion that springs can save you in an 'upset' scenario?
Non PC PLOD - Thank you - I forgot to mention that aspect which of course would be flying the aircraft contrary to the way it was designed to be flown.
G.
You must be aware of those three certainties in aviation - the three laws...
1. Sod's Law - If it can happen then it will happen
2. Murphy's Law - If it's possible for someone to put something together the wrong way then they will.
3. The Jammy Toast Law - If you drop a piece of jammy toast then it will land jammy side down. (which, translated means if you trust to luck then don't be surprised if you are disappointed.)
I beg you to drag yourself away from your Eurocentric understanding of our world. My 394 students come from 52 different countries and whilst you may have a standard of competency equivalent to 'acceptable' most out there do not and only escape the need for more training courtesy of a world that uses a 'tick-box system in a'compliance' dominated world.
I would like to keep my boss happy by keeping pictures of wrecked AW139's off the front pages of the newspapers and to do that we need to keep those that are new to complex helicopters clear of areas that 'bite'.
What say you of the notion that springs can save you in an 'upset' scenario?
Non PC PLOD - Thank you - I forgot to mention that aspect which of course would be flying the aircraft contrary to the way it was designed to be flown.
G.
Bravo -
"A quick dab on the FTR" (as you put it), - if the pilot is pushing significantly against the springs at the time (eg overcoming flapback during transition to forward flight ) will potentially result in a sudden nose-down jerk through the controls as they de-clutch. Clearly this could have serious negative consequences.
"A quick dab on the FTR" (as you put it), - if the pilot is pushing significantly against the springs at the time (eg overcoming flapback during transition to forward flight ) will potentially result in a sudden nose-down jerk through the controls as they de-clutch. Clearly this could have serious negative consequences.
If you don't advocate 'flying against the springs', what technique would you suggest for manual flying? a) Continually pressing the FTR (i.e. 'floppy sticking')? Just like in the G-LPAL accident? No thanks. Or b) by continuously trimming the attitude with the 'cooly hat'? Unfortunately, trimming the aircraft like that is too sluggish for many of the more, dynamic manual manoeuvres. Is there another option? If so, I'd love to hear it.
I suspect that is another case of poor terminology in the EHEST report. Will the springs help with an unusual attitude? No. But might they help with the onset of disorientation? Yes, maybe. (i.e. releasing the pressure on the cyclic will return the aircraft to a wings level attitude).
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B73
Dabbing the FTR with cyclic displaced - I repeat, not the way the aircraft was designed to be flown.
G-LPAL - if you are blaming that accident on the use of FTR then I suggest you re-read the AAIB report. FTR played a part but only because it was used inappropriately (i.e. in IMC without careful attitude monitoring).
The 139 is designed to use the FTR for 'manoeuvring' and the beeper for the corrections or small attitude changes.
When you are trimmed into a turn and suffer disorientation you can safely let go of the cyclic and - hey presto you are in a stable turn with no sudden change of attitude to further upset those canal things in the middle ear.
G.
G-LPAL - if you are blaming that accident on the use of FTR then I suggest you re-read the AAIB report. FTR played a part but only because it was used inappropriately (i.e. in IMC without careful attitude monitoring).
The 139 is designed to use the FTR for 'manoeuvring' and the beeper for the corrections or small attitude changes.
When you are trimmed into a turn and suffer disorientation you can safely let go of the cyclic and - hey presto you are in a stable turn with no sudden change of attitude to further upset those canal things in the middle ear.
G.
Sorry for labouring the point but can you confirm that this is the 'official' Agusta advice? When the aircraft is flown manually then the FTR must be pressed at all times whilst 'manoeuvring'.
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The 139 helicopter is designed in such a way that you can use any of the three trim techniques:
1. Pressing the FTR, selecting the required attitude, and releasing the FTR again.
2. Using the beeper trims on cyclic and collective to change reference attitudes (and other data)
3. Pushing against force trim springs (fly through).
Each technique has its place in different circumstances - none of the three is always the most appropriate in every situation. I use all three. I think the key is working out which technique is best in which circumstance.
1. Pressing the FTR, selecting the required attitude, and releasing the FTR again.
2. Using the beeper trims on cyclic and collective to change reference attitudes (and other data)
3. Pushing against force trim springs (fly through).
Each technique has its place in different circumstances - none of the three is always the most appropriate in every situation. I use all three. I think the key is working out which technique is best in which circumstance.
Just like the 365 (apart from no collective FTR on mine) - so not completely unique to 139.
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Fly through
I'm not going to enter a battle with my colleague because I have only my experiences to go on. I was the very first SFI to be trained by AW and had the benefit of being taught by the then CSFI. I teach as I was taught and do not teach the 'fly through' technique, in fact I try to stamp it out and teach as I was taught. This business of 'fly through' has gained added resonance (in my opinion) as a result of the debate about the mismanagement of automation. As I said in an earlier post I sat and watched last week whilst a recurrent training 'student' took off against the spring and then engaged the ALT A, the IAS, the NAV and let go of the cyclic. The nose pitched up, the airspeed dropped enough for the FD modes to drop out and we very nearly bought the farm. I'm sure you are all aware of the 'design for success' concept rather than accepting a 'latent error' in the shape of an inappropriate technique. If we teach the right way at the beginning of the course there is a good chance they won't need the 'fly through at all but as I say, I am no expert, I just have some experience. An expert is someone who knows everything and only my wife knows everything (and maybe my mother).
As always rules are for the obedience of fools (newbies in this case) and the guidance of wise men (experienced 139 folk). I will not argue that point. I also, for the record, teach that upon entering IMC you come off the FTR and use the beeper. I find that the who are weak in IMC ops often try to engage AP modes with the FTR depressed resulting in an unintentional roll input (and sometimes a pitch one too) that gets scarily out of hand. I've even seen pilots getting close to inverted in the few seconds to took to understand their error.
Please don't refer to the use of the FTR as a 'floppy stick' technique. As soon as you remove your hand the stick will remain in that position unlike a true floppy stick a la B206 for example. SAS remains to make the use of FTR whilst manoeuvring an entirely pleasant experience, more so in the real aircraft than the sim. You should give it a go instead of thrashing the trim system to death by using fly through for the only way to return the aircraft to the trimmed state is then to use the FTR. As I say, not the way the aircraft was designed to be used.
G.
As always rules are for the obedience of fools (newbies in this case) and the guidance of wise men (experienced 139 folk). I will not argue that point. I also, for the record, teach that upon entering IMC you come off the FTR and use the beeper. I find that the who are weak in IMC ops often try to engage AP modes with the FTR depressed resulting in an unintentional roll input (and sometimes a pitch one too) that gets scarily out of hand. I've even seen pilots getting close to inverted in the few seconds to took to understand their error.
Please don't refer to the use of the FTR as a 'floppy stick' technique. As soon as you remove your hand the stick will remain in that position unlike a true floppy stick a la B206 for example. SAS remains to make the use of FTR whilst manoeuvring an entirely pleasant experience, more so in the real aircraft than the sim. You should give it a go instead of thrashing the trim system to death by using fly through for the only way to return the aircraft to the trimmed state is then to use the FTR. As I say, not the way the aircraft was designed to be used.
G.
Last edited by Geoffersincornwall; 6th Jan 2016 at 13:46. Reason: expanding on the point
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Geoffers,
I just think its a bit strong to say you should never use fly-through. EG.: I find it the perfect way to fly a manual ILS. Gentle pressure against the cyclic for a couple of seconds then release is a much easier way of making a 1 or 2 degree heading correction than by using either of the other techniques.
You just need to use it at appropriate times!
I think the FCOM is in hand, but it is a massive undertaking for the poor bloke who has to write it! Probs be a while yet!!
I just think its a bit strong to say you should never use fly-through. EG.: I find it the perfect way to fly a manual ILS. Gentle pressure against the cyclic for a couple of seconds then release is a much easier way of making a 1 or 2 degree heading correction than by using either of the other techniques.
You just need to use it at appropriate times!
I think the FCOM is in hand, but it is a massive undertaking for the poor bloke who has to write it! Probs be a while yet!!
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Non PC
I don't think I said NEVER use it and even went along with the idea that in the hands of the experienced it is not a problem as they have worked out when it can be handy, as you say. They are also fully at home in the 139 by this time.
The problem comes with teaching it. The times when it is appropriate are nuanced and applied to gain benefit not just because 'I always fly this way'. If you have taught those coming from a background flying Russian helicopters then I'm sure you know what I mean. I believe it is one step too far in the context of a very tight syllabus that only just manages to cope with the marginal candidate and is severely tested when teaching via an interpreter. The pressure of learning to fly in a glass cockpit with 3-axis AP/FD with FMS already makes the learning curve pretty steep.
My recent experience with the two recurrent training pilots convinces me that I am on the right track. In the context of autopilot mismanagement the 'fly-through' is a trap waiting to capture those unfamiliar with the implications of an mistake in IMC conditions. As we know most of our charges are most definitely unfamiliar with flight in IMC.
As I said earlier I am not setting myself up as an expert on this matter, I only wish to pass on the benefit of my experience and seek to hear the views of others. As I was taught to fly this way I assumed everybody else was too. Maybe I was wrong.
G.
The problem comes with teaching it. The times when it is appropriate are nuanced and applied to gain benefit not just because 'I always fly this way'. If you have taught those coming from a background flying Russian helicopters then I'm sure you know what I mean. I believe it is one step too far in the context of a very tight syllabus that only just manages to cope with the marginal candidate and is severely tested when teaching via an interpreter. The pressure of learning to fly in a glass cockpit with 3-axis AP/FD with FMS already makes the learning curve pretty steep.
My recent experience with the two recurrent training pilots convinces me that I am on the right track. In the context of autopilot mismanagement the 'fly-through' is a trap waiting to capture those unfamiliar with the implications of an mistake in IMC conditions. As we know most of our charges are most definitely unfamiliar with flight in IMC.
As I said earlier I am not setting myself up as an expert on this matter, I only wish to pass on the benefit of my experience and seek to hear the views of others. As I was taught to fly this way I assumed everybody else was too. Maybe I was wrong.
G.
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My previous post....
.... in particular the last line has been worrying me. From the responses so far I am getting the impression that here may be many AW139 pilots out there who are using the 'fly-through' technique perhaps more than they should.
The argument in EH9, The EHEST document on Management of Automation asserts that the fly through technique is to be used in preference when making a turn because a stable condition with wings level can be assured simply by letting go of the cyclic. This may have been logical thing to do in the days of helicopters that rely on a simple SAS but it is not logical when you are flying a coupled 3 axis AP/FD system in a latest generation helicopter.
For a start the way to fly the aircraft is primarily by using the coupled modes. If you choose to use the beeper (no HDG mode engaged) instead of the HDG knob (in HDG mode) you are in fact doing exactly the same thing as using the HDG mode. In both cases the cyclic remains in the same position throughout.
The 139 has the added facility of being able to 'drive the heading bug to a new datum via the beeper trim in which case it will use the appropriate angle of bank for a rate 1 turn until settling on the new heading.
The idea that whilst using 'fly-through' you can respond to an upset by letting go of the cyclic is fatally flawed in the 139. The most common way we see pilots arriving at an AP-OFF situation is by their mis-selection of the SAS REL button whilst going for the FD S/BY button. We, at the same time as teaching how to manage the FD Modes, teach the industry standard response to an apparent failure of the system to do as we ask of it and that is to revert to 'manual' flying until we have understood what went wrong. What I witnessed recently was a pilot doing exactly as we wanted him to do except he found the wrong button and took out his AP's. Very nasty as he was IMC. The subsequent red screen was acutely embarrassing.
The answer as to why there is a propensity to make this mis-selection may lay in the way other types make use of cyclic buttons. Some have CAS Message cancellation buttons for example. If you are flying two types and they are very different in this respect (i.e. they have buttons in the same place but they do different things) then we have accidents waiting to happen.
The question of 'Flying-through' being in any way logical in today's complex helicopters is called into question insofar as we do not apply the same logic to the collective. If the power is set at 'cruise' and the collective moved against the spring for any climb or descent then the EHEST logic would allow us to take our hands off the controls when we encounter an 'upset' and we would be returned to 'wings level in level flight'. We don't though, do we! Do we? I hope not.
We never move the collective without pressing the FTR button first. All I'm saying is that we should be applying the same philosophy with moving the cyclic. When a stable condition has been achieved then it's over to the beeper.
I am mindful of the fact that there are many 139 pilots who achieved their TR somewhere other than at a factory school. Maybe that's why they didn't get the message. Maybe you did attend a factory school or were taught by a factory TRI or SFI and were taught the 'fly-through' technique, If so please let me know. It would be handy to know the size of the problem.
G.
The argument in EH9, The EHEST document on Management of Automation asserts that the fly through technique is to be used in preference when making a turn because a stable condition with wings level can be assured simply by letting go of the cyclic. This may have been logical thing to do in the days of helicopters that rely on a simple SAS but it is not logical when you are flying a coupled 3 axis AP/FD system in a latest generation helicopter.
For a start the way to fly the aircraft is primarily by using the coupled modes. If you choose to use the beeper (no HDG mode engaged) instead of the HDG knob (in HDG mode) you are in fact doing exactly the same thing as using the HDG mode. In both cases the cyclic remains in the same position throughout.
The 139 has the added facility of being able to 'drive the heading bug to a new datum via the beeper trim in which case it will use the appropriate angle of bank for a rate 1 turn until settling on the new heading.
The idea that whilst using 'fly-through' you can respond to an upset by letting go of the cyclic is fatally flawed in the 139. The most common way we see pilots arriving at an AP-OFF situation is by their mis-selection of the SAS REL button whilst going for the FD S/BY button. We, at the same time as teaching how to manage the FD Modes, teach the industry standard response to an apparent failure of the system to do as we ask of it and that is to revert to 'manual' flying until we have understood what went wrong. What I witnessed recently was a pilot doing exactly as we wanted him to do except he found the wrong button and took out his AP's. Very nasty as he was IMC. The subsequent red screen was acutely embarrassing.
The answer as to why there is a propensity to make this mis-selection may lay in the way other types make use of cyclic buttons. Some have CAS Message cancellation buttons for example. If you are flying two types and they are very different in this respect (i.e. they have buttons in the same place but they do different things) then we have accidents waiting to happen.
The question of 'Flying-through' being in any way logical in today's complex helicopters is called into question insofar as we do not apply the same logic to the collective. If the power is set at 'cruise' and the collective moved against the spring for any climb or descent then the EHEST logic would allow us to take our hands off the controls when we encounter an 'upset' and we would be returned to 'wings level in level flight'. We don't though, do we! Do we? I hope not.
We never move the collective without pressing the FTR button first. All I'm saying is that we should be applying the same philosophy with moving the cyclic. When a stable condition has been achieved then it's over to the beeper.
I am mindful of the fact that there are many 139 pilots who achieved their TR somewhere other than at a factory school. Maybe that's why they didn't get the message. Maybe you did attend a factory school or were taught by a factory TRI or SFI and were taught the 'fly-through' technique, If so please let me know. It would be handy to know the size of the problem.
G.
Last edited by Geoffersincornwall; 8th Jan 2016 at 17:47. Reason: explanation improved
The most common way we see pilots arriving at an AP-OFF situation is by their mis-selection of the SAS REL button whilst going for the FD S/BY button.
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I try to include a total screen failure, manual raw data ILS on the ESIS (S/by horizon system) when doing a TR on the 139.
In my next life I am hoping to come back as a sim instructor, if there are no vacancies I will settle for God.
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Crab & Max
Crab - I think there is an unfortunate combination of factors. I would have thought a wiser approach would have been to reduce the impact of inadvertent selection by making it a single push for one AP and a second to remove both. The training is a matter of practice but if the course is thin on the use of FD modes then you don't get much practice. It's then up to the individual to do what he/she can to improve familiarity. The fact that other types either flown previously or simultaneously have cyclic buttons that add to the confusion doesn't help.
Max - I could of course be realistic and fail one screen but that would pointless if the objective is to train on the ESIS for the main DH is available in composite format. Less realistic would be to fail both screens on the pilot side but then the staff answer is to pass control to the co-pilot. Better all round to bite the bullet and imagine a poorly managed Double DC Gen fail scenario in which the voltage falls below the threshold for the DU's and there you have it - the ESIS alone to get you home.
I only give that to those that are well able to deliver something approaching success. That success gives their confidence a boost as well as an idea about the usefulness of the ESIS. Of course if you have a better way of teaching the use of the ESIS during an ILS approach then I would love to hear it. Those of us that have studied accidents and incidents can point to many instances when multiple systems have failed despite their apparent invulnerability.
http://www.caa.si/fileadmin/user_upl...-104_B__R1.pdf
The AP system on the 139 has already demonstrated some vulnerabilities in this respect.
G.
Max - I could of course be realistic and fail one screen but that would pointless if the objective is to train on the ESIS for the main DH is available in composite format. Less realistic would be to fail both screens on the pilot side but then the staff answer is to pass control to the co-pilot. Better all round to bite the bullet and imagine a poorly managed Double DC Gen fail scenario in which the voltage falls below the threshold for the DU's and there you have it - the ESIS alone to get you home.
I only give that to those that are well able to deliver something approaching success. That success gives their confidence a boost as well as an idea about the usefulness of the ESIS. Of course if you have a better way of teaching the use of the ESIS during an ILS approach then I would love to hear it. Those of us that have studied accidents and incidents can point to many instances when multiple systems have failed despite their apparent invulnerability.
http://www.caa.si/fileadmin/user_upl...-104_B__R1.pdf
The AP system on the 139 has already demonstrated some vulnerabilities in this respect.
G.
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I believe I heard about a 4 x DU fail due to a wiring loom issue behind the instrument panel somewhere in Scandinavia. Fortunately the crew was just coming out of the cloud as it happened. So, its not a completely far-fetched scenario! I like to get students to do at least one approach on ESIS during the training - it helps to give confidence in their operation of the helicopter if they know they can get home using just one small part of the equipment!
Crab - you are right: most dangerous button on the helicopter! Trouble is, it is a certification requirement - (probably again a throwback to stoneage AFCS). Most experienced pilots say they have accidentally pushed it, or been on board when someone else has accidentally pushed it at least once! ......So, guess where the button is on the new 169??? Answers on a postcard!
Crab - you are right: most dangerous button on the helicopter! Trouble is, it is a certification requirement - (probably again a throwback to stoneage AFCS). Most experienced pilots say they have accidentally pushed it, or been on board when someone else has accidentally pushed it at least once! ......So, guess where the button is on the new 169??? Answers on a postcard!
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Better all round to bite the bullet and imagine a poorly managed Double DC Gen fail scenario in which the voltage falls below the threshold for the DU's and there you have it - the ESIS alone to get you home.
If I understand it correctly, a 139 pilot will only need to fly an ILS on the ESIS in the event of a failure of either both AHRS or all 4 Display Units ? (All independent systems)
Would it not be better to introduce and teach the ESIS as a tertiary instrument for cross checking information from the primary and secondary systems and acting as an umpire in the event of conflicting information between them.
Of course, recurrent students should be made to fly on it just for ****s and giggles........
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Max
My apologies for an earlier post, I took offence at your last comment but then thought better of it. I fear you have been brutalised by poor sim instruction which is sad but I know it goes on. If you wish to PM me with some details I'll add it to my list of horror stories. It is a shame that so little auditing of sim instruction goes on For that reason this kind of abuse goes undetected. I'm thinking of becoming an auditor when I retire 
The objective of the 'screens-out' exercise is to familiarise the student with an unusual instrument that he has probably never come across before. The ESIS is not just an AH. It's also an IAS indicator, a VSI, an Altimeter and a compass and is also capable of providing VOR/ILS data/guidance.
When the student is forced to use it as the sole means of reference he/she appreciates just how straightforward it is so the concept of a total screen failure becomes less intimidating.
I don't teach that exercise to recurrent students unless requested. I take your point about using the ESIS as a referee but there is only so much time in a TR course and so many pilots require some remedial IF training during that segment of the course. Perhaps we can talk about that kind of thing on another thread. Right now I am trying to create a good enough argument for EHEST to at least add a correction to their booklet to say that their list of 'good tips' applies only to the EC225 for it certainly doesn't apply to the AW139. Maybe they would also reconsider advising pilots to rely on the stabilisation system to deliver recovery during a 'fly-through' manoeuvre. It is an archaic concept now that we are discussing the mismanagement of automation in the context of the latest generation of complex helicopters.
G.
The objective of the 'screens-out' exercise is to familiarise the student with an unusual instrument that he has probably never come across before. The ESIS is not just an AH. It's also an IAS indicator, a VSI, an Altimeter and a compass and is also capable of providing VOR/ILS data/guidance.
When the student is forced to use it as the sole means of reference he/she appreciates just how straightforward it is so the concept of a total screen failure becomes less intimidating.
I don't teach that exercise to recurrent students unless requested. I take your point about using the ESIS as a referee but there is only so much time in a TR course and so many pilots require some remedial IF training during that segment of the course. Perhaps we can talk about that kind of thing on another thread. Right now I am trying to create a good enough argument for EHEST to at least add a correction to their booklet to say that their list of 'good tips' applies only to the EC225 for it certainly doesn't apply to the AW139. Maybe they would also reconsider advising pilots to rely on the stabilisation system to deliver recovery during a 'fly-through' manoeuvre. It is an archaic concept now that we are discussing the mismanagement of automation in the context of the latest generation of complex helicopters.
G.
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HC - as requested
http://easa.europa.eu/essi/ehest/wp-..._EHEST_HE9.pdf
You will observe in para 2.4.3 that it advises pilots not to trim into the turn when using the basic AFCS systems. Later in a subsequent paragraph about 3 & 4-axis systems it doesn't provide any similar 'tips'. This leaves pilots with the impression that the 'do not trim into a turn' philosophy remains as the FD modes are built upon a basic AFCS system.
It certainly seems that there are many AW139 pilots who haven't got the message that trimming into the turn in normal stabilised flight is the preferred way to go. The French have even made trimming into a turn during a flight test a 'fail' point according to many of my French students.
We need the HE9 booklet to expressly say that trimming into the turn is the preferred way to go if the HDG mode is not being used directly.
G.
You will observe in para 2.4.3 that it advises pilots not to trim into the turn when using the basic AFCS systems. Later in a subsequent paragraph about 3 & 4-axis systems it doesn't provide any similar 'tips'. This leaves pilots with the impression that the 'do not trim into a turn' philosophy remains as the FD modes are built upon a basic AFCS system.
It certainly seems that there are many AW139 pilots who haven't got the message that trimming into the turn in normal stabilised flight is the preferred way to go. The French have even made trimming into a turn during a flight test a 'fail' point according to many of my French students.
We need the HE9 booklet to expressly say that trimming into the turn is the preferred way to go if the HDG mode is not being used directly.
G.
