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Simulator Training for strong crosswind landings

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Simulator Training for strong crosswind landings

Old 19th Jun 2014, 07:10
  #81 (permalink)  
 
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Air Rabbit. I for one thoroughly enjoy reading (and learning ) from your posts. But please break up the large amount of text with appropriate paragraphing. This contributor's eyes reading through trifocals start to glaze over after being forced to read line after line without a break. I wouldn't be surprised if others echo my thoughts but are too kind to say something. The pity is you write such thoughtful stuff and yet some may turn away from it due eye fatigue. No offence intended.
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Old 19th Jun 2014, 16:42
  #82 (permalink)  
 
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Hi Judd

I certainly don’t take any offence, and actually, I appreciate your honesty. In fact, I am fully aware that I use “a lot” of words to get my points across … and that comes from my educational and instructing background … where, over the years, I’ve found that some folks see/hear and understand the same point(s), but quite often do so from differing perspectives – meaning that to ensure the widest level of understanding, it is usually better to fully explain the points desired, and do so preferably from more than one perspective, or using more than one approach to the subject. The resulting problem is being … well … “wordy,” and I’m certainly guilty of that.

I will attempt to remember what you’ve said and post comments that are structured with a bit more space to avoid the “eye problems.” But, knowing me, even with all the good intentions I may muster, I am relatively sure that, particularly on subjects that are of significant importance to me, I’m likely to open the flood gates. Again, thanks for the honesty and for the compliment it contained.
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Old 20th Jun 2014, 17:25
  #83 (permalink)  
 
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ZFT
There is a requirement on an initial EASA evaluation for the operator’s evaluation team to sign and submit an attestation to EASA that confirms that, amongst other items the FFS flying qualities represents theaeroplane being simulated (GM1 ORA.FSTD.115 Part C).
FAA Part 60 has the same requirement:
§60.15 Initial qualification requirements.
(b) The management representative described in §60.9(c) must sign a statement (electronic signature is acceptable for electronic transmissions) after confirming the following:
(1) The performance and handling qualities of the FSTD represent those of the aircraft or set of aircraft within the normal operating envelope. This determination must be made by a pilot(s) meeting the requirements of paragraph (d) of this section after having flown all of the Operations Tasks listed in the applicable QPS appendix relevant to the qualification level of the FSTD. Exceptions, if any, must be noted. The name of the person(s) making this determination must be available to the NSPM upon request.
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Old 20th Jun 2014, 17:44
  #84 (permalink)  
 
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There of course are always at least two sides to any subject. Years ago, a local Director of Operations went to fly a major airlines “qualified” MD-80 simulator. During the engine out work, he stated that the simulator needed a lot of rudder to keep the aircraft straight. Upon further investigation, it was found that both engines center of thrust were about 10 feet farther out than they should have been.

I had a new dry lease crew come out of the simulator and complain it did not handle correctly. When I asked, I was told it was “not stable in the horizontal axis!” I replied, “Lateral or longitudinal, rotation of, or rotation around?” The crew walked away…

AirRabbit has done a great job in this topic, and reading between the lines (and adding my own 2 cents) I would say that simulation training is more of a group (pilots, instructors, certification, evaluation, maintenance, data gathering) effort than operating the actual aircraft.
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Old 20th Jun 2014, 20:34
  #85 (permalink)  
 
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Originally Posted by mnttech
There of course are always at least two sides to any subject. Years ago, a local Director of Operations went to fly a major airlines “qualified” MD-80 simulator. During the engine out work, he stated that the simulator needed a lot of rudder to keep the aircraft straight. Upon further investigation, it was found that both engines center of thrust were about 10 feet farther out than they should have been.
Quite some time ago now, when I first qualified on the DC-9, the guys were going to issue me a DC-9 Type with my initial ATP, but it was going to be limited to Center Thrust. When I questioned them on that issue, they initially explained that the DC-9 was a Center Thrust airplane, and started to explain to me that it was because an engine out didn’t require a lot of rudder! One of the instructors happened to be standing right behind me – and I turned to get his reaction to that statement. He was dumbfounded! He insisted that they call the FAA HQ in Washington to check. The guy in DC said it was because the Airplane Type Certification Data Sheet had no “minimum control speed with an engine out” and gave the reference page.

The guys in the office I was in, pulled that manual off the shelf, and turned to the referenced page … and sure enough, there was no value typed in that spot! So the instructor grabbed the book and turned back to the previous section, which was Douglas DC-8, and turned to the same page. He found that there was no entry typed into the same location for that airplane. He merely pointed to the blank entry and asked if the DC-8 was also “limited to centerline thrust.” The guy on the phone asked the bloke in DC to turn to that same referenced page in the DC-8 section … and, after a couple of shuffled feet, he agreed that they could issue my rating and the ATP without a Centerline Thrust limitation. After that phone call, all the instructors and students in the office were describing the almost full rudder pedal deflection it took to maintain heading with an engine failure (simulated) on takeoff … and that was in a DC-9-15 (“-10 series” – no leading edge slats) and at training weights, speeds, and thrust settings. This was a training program that did not use a simulator at all. All of the training and the check was in the airplane.

Additionally, what I have seen, while it is certainly not in every case, but in a significant portion of cases, where crew members complain about the simulator, they are complaining because they are attempting to fly the simulator – as they remember their training – and not flying the airplane. Unfortunately, again, in my “not-so-humble-opinion,” at least some of the “training” that passes today is training to get through the training program or the check in the simulator … where at least some of the training, perhaps a lot more than “some,” is “default training” where the instructors rely waaaay too much on the simulator to do the training, while they simply push the buttons and type in the scenarios. These students then go out to fly the airplane – get comfortable in it – and come back to the simulator with a view toward trying to remember and recapture the feelings, the sights, the sounds, and their responses (as they remember them) in an attempt to fly the simulator … as they remember it. They normally wind up using a combination of what simulator techniques they remember and what they’ve come to expect in the airplane. As a result, they get confused and frustrated … and because they “know” they can fly the airplane, they blame their problems on the simulator.

Originally Posted by mnttech
I had a new dry lease crew come out of the simulator and complain it did not handle correctly. When I asked, I was told it was “not stable in the horizontal axis!” I replied, “Lateral or longitudinal, rotation of, or rotation around?” The crew walked away…
This is the kind of complaint that I was attempting to describe, above. It sounds like they really don’t know what the problem was. They didn’t even know what axis was involved. What they probably DID know was that they had trouble flying the simulator. Since they don’t have a problem flying the airplane … the problem MUST be with the simulator. They are completely unaware of why that is … when it is highly likely that the "real" problem is that they were incorrectly or incompletely trained.

Originally Posted by mnttech
I would say that simulation training is more of a group (pilots, instructors, certification, evaluation, maintenance, data gathering) effort than operating the actual aircraft.
THAT is the point that a lot of folks completely miss. If the work product made available from any of those sources has some rough edges, those edges will come into play in the simulator – it almost HAS to – but a competently trained instructor would recognize what the student is doing to compensate for the particular “rough edge,” and would explain what was happening, why it was happening that way, and instruct the student on the proper, airplane generated, in-put cues and what that student needs to do to respond correctly. If the student does what he/she was told to do by that competently trained instructor, that student will find that the control application response described by that instructor will provide the correct (desired) simulator response ... AND will get the correct response when flying the airplane.

When that student gets to the airplane, and sees the same circumstances, what is recognized will be like the instructor’s description, and the control applications described by that instructor will provide the proper airplane response initiated by that student. NOW, when that student returns to the simulator, and the same incorrect input cue is displayed by the simulator, that student should know what control application is necessary, apply it to the simulator controls, and the simulator will respond correctly … everyone is happy. All because of the competence of that instructor! That is what instructing is all about.

Last edited by AirRabbit; 21st Jun 2014 at 03:37.
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Old 21st Jun 2014, 11:27
  #86 (permalink)  
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but a competently trained instructor would recognize what the student is doing to compensate for the particular “rough edge,” and would explain what was happening, why it was happening that way, and instruct the student on the proper, airplane generated, in-put cues and what that student needs to do to respond correctly
I must be dumb because I cannot visualise what you mean. There are some professional simulator instructors who have never flown the real aeroplane they are instructing for in the simulator. After all not all simulator instructors have flown the A380 or a Boeing 787 yet have passed the interviews and a type rating course on the simulator and certified competent to test and instruct.

In fact there are many airline retired simulator instructors who may only "fly" their specific simulator twice a year for a couple of hours each time to maintain the minimum currency required by the regulator. I bet the majority of that is on automatic pilot as well.

In my experience it is rare to see a simulator instructor whether he is a current check pilot or simply a retired pilot, actually take a control seat and demonstrate to a candidate how to conduct a high speed rejected take off with all its after stopping SOP's. Or demonstrate to a candidate that is having problems with an engine failure, manual reversion, low level circling approach, or all flaps up landing. Most of the time the simulator instructor has a rigid set of SOP to stick to during a type rating sequence or recurrent training sequence. He sits back in the instructor panel and reads the syllabus and presses the required buttons on the IOS. The syllabus is usually approved by the local regulator and due to limitations of time available and cost of simulator time, there is rarely time for extra handling training that may be needed. Certainly he won't have the time to change seats with the candidate and show him how it should be done.

I find it difficult to get my head around the points that some contributors to the debate say, when they mention instructors need to be familiar with the perceived differences between the real aircraft and what is experienced in the simulator. This is especially so when the same instructors could have conceivably not flown the real aircraft for ten years or more.
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Old 21st Jun 2014, 19:36
  #87 (permalink)  
 
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Originally Posted by Centaurus
I must be dumb because I cannot visualise what you mean.
Centaurus, my friend, of all the participants on this forum, you would be among the very last to whom I would attribute “dumb” as an accurate description.
Originally Posted by Centaurus
There are some professional simulator instructors who have never flown the real aeroplane they are instructing for in the simulator. After all not all simulator instructors have flown the A380 or a Boeing 787 yet have passed the interviews and a type rating course on the simulator and certified competent to test and instruct.
…which, I believe, is a part – a substantial part – of the problem. That problem being someone has determined that those who have the kind of “training” and “experience” you have described is all that is necessary to be deemed competent and experienced enough to convey their acquired “competency” and “experience” to others who will then be deemed competent enough take the airplane and all of its passengers and cargo across whatever distance, at whatever altitude and airspeed, through whatever meteorological conditions, without care or concern for the safety and efficiency of that effort.
Originally Posted by Centaurus
In fact there are many airline retired simulator instructors who may only "fly" their specific simulator twice a year for a couple of hours each time to maintain the minimum currency required by the regulator. I bet the majority of that is on automatic pilot as well.
Of course, those retired airline pilots who have taken positions as “simulator instructors," do have some (perhaps a substantial amount) of airplane time on the respective airplane, on which they can depend, or at least, to which they may refer, when they make judgments with respect to what and how they are instructing in the simulator. Clearly, the longer the time between “the real airplane” and “the simulated airplane,” the less value results from the dulled sharpness of the memories that are formulating the information being relayed. This results in the value of what is instructed being inversely proportional to the recency of any and all experience gained in having regularly performed those same tasks now being instructed. And, it should be distinctly recognized that having to depend on “the automatic pilot” to get through the short time required for that so-called “currency,” is a pitiful substitution for the competency and experience that should be relied upon to achieve the quality of whatever “instructing” is being attempted.
Originally Posted by Centaurus
In my experience it is rare to see a simulator instructor whether he is a current check pilot or simply a retired pilot, actually take a control seat and demonstrate to a candidate how to conduct a high speed rejected take off with all its after stopping SOP's. Or demonstrate to a candidate that is having problems with an engine failure, manual reversion, low level circling approach, or all flaps up landing. Most of the time the simulator instructor has a rigid set of SOP to stick to during a type rating sequence or recurrent training sequence. He sits back in the instructor panel and reads the syllabus and presses the required buttons on the IOS. The syllabus is usually approved by the local regulator and due to limitations of time available and cost of simulator time, there is rarely time for extra handling training that may be needed. Certainly he won't have the time to change seats with the candidate and show him how it should be done.
There is a “saying” in the US … “you get what you pay for.” The accuracy of this “saying,” comes to realization – unfortunate realization – in recognizing the accuracy of your comment. Those posing those SOPs, structuring those training sequences … (i.e., “if it’s the 4th training session we must get through RTOs and Emergency Descents” … even though normal landings that were addressed on the 2nd training session are still misunderstood and unsatisfactory) are more interested in what looks good on paper, and what looks good to those who pay the bills, than anything else. In fact, the instructors that we do use are unbelievably good at putting the students through just enough rote-memory-practice that they are able to squeak through a demonstration. Unfortunately, in doing so, invariably, there will be several student pilots who “complete” the course with improper or incomplete or misunderstood cause/effect relationships with improper or incomplete or misunderstood actions that they may believe to be appropriate or believe must be taken … unfortunately … ONE such student is all it takes to generate bent metal and spilled blood … and, if … or perhaps more properly … when … the appropriate circumstances combine in just the right sequence … IT WILL HAPPEN … and we are completely at the mercy of “lucky stars” or “accidental correctness” to avoid such tragedies.
Originally Posted by Centaurus
I find it difficult to get my head around the points that some contributors to the debate say, when they mention instructors need to be familiar with the perceived differences between the real aircraft and what is experienced in the simulator. This is especially so when the same instructors could have conceivably not flown the real aircraft for ten years or more.
I could not agree with you more, my friend. It borders on the impossible for any competent aviator to misunderstand the necessary differences of having pilots who pointedly perceive, understand, and act accordingly with respect to a simulated airplane’s presentation of contrived events and their response to those inputs … and their being able to correctly perceive, understand, and act when the real airplane contributes in-put cueing to pilots … day-in and day-out. Unfortunately, almost any list of accidents, which may be generated by any who read these words, are replete with questions like, “why didn’t they recognize what was happening?” I think we need to seriously look at who, how, when, with what, to what end, do we, as an industry, conduct pilot training. That look and those questions simply have to address the tools, the persons who use those tools, and training of those persons to use those tools, and what kind of competency do we expect those persons to achieve in order to competently and completely train the pilots who will be putting all that training into use. I don’t think it will happen if we continue on the path that we all find ourselves at the moment.

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Old 2nd Jul 2014, 16:42
  #88 (permalink)  
 
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ZFT says; "Simulation is nothing but one big con job but apart from the obvious there is one other massive benefit. It is the perfect and only environment to do things wrong, either unintentionally and hopefully learn from it or deliberately just to see the result (we have a FSTD with very accurate post stall modelling and every trainee experiences a deep tail stall and recovery) but of course, the FSTD must be as accurate as it can be else the FSTD is always wrong, not the trainee!"


I have a question to both ZFT and AirRabbit.


How can you be sure that the post stall modelling is correct and that your simulator replicates the real aircraft's behaviour post stall? It is my understanding that no large transport aircraft is tested in the post stall regime (especially in a deep stall) and therefore all simulators use extrapolated data, aerodynamic modelling and wind tunnel data.


I would be very interested in your views.
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Old 3rd Jul 2014, 07:49
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Chiming in a bit late on this thread (the video scared the F out of me) So, I must apologize, as this is an extensive thread.

I have been in the sim at Alteon quite a bit for RNP procedure validation, and we certainly did a bit of crosswind simulation depending on the location.

One thing I had noticed, looking around, was very seldom did I see a sim on full motion, in fact when we went full motion they had some 'concerns'. As a general question, when training in the sim, are they using full motion?

In the sim, I didnt experience the severe gusting crosswinds (as shown in the video) We took some of the settings to the limits, but didnt get that severe gusting effect on full motion. We did get sideways, but I dont remeber the ac rolling around like that.

Again, late to the party, so apologies in advance.
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Old 3rd Jul 2014, 10:01
  #90 (permalink)  
 
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Hi underfire,
but didn't get that severe gusting effect on full motion. We did get sideways, but I don't remember the ac rolling around like that.
I'm glad you notice the same limitations also.

Since the sim motion is limited to the amount of travel of the jacks, and at full jack extension / retraction the sim motion must approach zero - then it can't faithfully imitate real life. Your sideways acceleration is simulated by rolling (banking) the cab but at the same time keeping strong visual clues to being level. It sounds like you can sense the sim cab rolling also. Glad I'm not alone.
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Old 3rd Jul 2014, 13:35
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Further to my post above on the simulation of post stall behaviour, and at the risk of thread drift (this thread has evolved into a very interesting discussion on simulator fidelity), may I offer the quote below from Captain William Wainwright's paper entitled "Airplane Upset Recovery, a test pilot's point of view".

QUOTE:-
USE OF SIMULATORS
We manufacturers were very concerned over the types of manoeuvres being flown in simulators and the conclusions that were being drawn from them. Simulators, like any computer system, are only as good as the data that goes into them. That means the data package that is given to the simulator manufacturer. And we test pilots do not deliberately lose control of our aircraft just to get data for the simulator. And even when that happens, one isolated incident does not provide much information because of the very complicated equations that govern dynamic manoeuvres involving non-linear aerodynamics and inertia effects.

The complete data package includes a part that is drawn from actual flight tests, a part that uses wind tunnel data, and the rest which is pure extrapolation. It should be obvious that firm conclusions about aircraft behaviour can only be drawn from the parts of the flight envelope that are based on hard data. This in fact means being not far from the centre of the flight envelope; the part that is used in normal service. It does not cover the edges of the envelope. I should also add that most of the data actually collected in flight is from quasi-static manoeuvres. Thus, dynamic manoeuvring is not very well represented. In fact, a typical data package has flight test data for the areas described in Table 1.

Table 1 Sideslip Angle of attack

SLATS OUT
All Engines Operating Around neutral Between 0°and 22°
Between + 15° and -15° Between 0° and 12°
One Engine Inoperative Between +8° and -8 Between 5° and 12°

SLATS IN, LOW MACH
All Engines Operating Around neutral Between 0° and 12°
Between +10° and -10° Between 2° and 9°
One Engine Inoperative Between +8° and -8° Between 2° and 8°

SLATS IN, HIGH MACH
All Engines Operating Around neutral Between 0° and 5°
Between +5° and -5° Between l° and 3°
One Engine inoperative Between +2° and -2° Between 1° and 3°

In other words, you have reasonable cover up to quite high sideslips and quite high angles of attack (AOA), but not at the same time. Furthermore, the matching between aircraft stalling tests and the simulator concentrates mainly on the longitudinal axis. This means that the simulator model is able to correctly reproduce the stalling speeds and the pitching behaviour, but fidelity is not ensured for rolling efficiency (based on a simplified model of wind tunnel data) or for possible asymmetric stalling of the wings. Also, the range for one engine inoperative is much less than the range for all engines operating and linear interpolation is assumed between low and high Mach numbers.

Wind tunnel data goes further. For example, a typical data package would cover the areas described in table 2. In fact, this is a perfectly adequate coverage to conduct all normal training needs. But it is insufficient to evaluate recovery techniques from loss of control incidents. Whereas, the training managers were all in the habit of demonstrating the handling characteristics beyond the stall; often telling their trainees that the rudder is far more effective than aileron and induces less drag and has no vices! In short, they were developing handling techniques from simulators that were outside their guaranteed domain.

Table 2 Sideslip Angle of attack

SLATS OUT From +18° to -18° From -5° to 25°
SLATS IN, LOW MACH From +18° to -18° From -5° to 12°
SLATS IN, HIGH MACH From + 8° to -8° From -2° to 8°

Simulators can be used for upset training, but the training should be confined to the normal flight envelope. For example, training should stop at the stall warning. They are “virtual” aircraft and they should not be used to develop techniques at the edges of the flight envelope. This is work for test pilots and flight test engineers using their knowledge gained from flight testing the “real” aircraft

END QUOTE

Captain Wainwright is Chief Test Pilot of Airbus Industrie. I quote from his full paper because I think sometimes we expect too much from simulators when it comes to manoeuvres at or beyond the edge of the flight envelope.

Simulator training in severe crosswinds is good up to a point, it can certainly be used to develop the correct technique even though the simulation of all the sensations experienced in the real aircraft may be lacking in some areas (as noted by some contributors in previous posts on this thread). However, I have grave concerns about simulator training post stall for the reasons Captain Wainwright has stated, hence my concern over ZFT's remarks about this.
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Old 3rd Jul 2014, 18:16
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Hi Bergerie1:

In reference to your quotes from Bill Wainwright …(I met Captain Wainwright when he was still at Airbus … although I understand he’s now moved to Boeing, and, of course, I wouldn’t desire to argue with his statements – particularly, as his vantage point is firmly, and rightly, based in the technicality of flight test data) … I would refer you to an earlier post of mine on this thread …

Originally Posted by AirRabbit
…today, I know we have at least one, and now, I understand, a second, transport category airplane simulator (the first one IS and I believe the second one is ALSO a B-737) that have an aerodynamic model installed that is accurate enough that the several test pilots (2 or 3 on the first, and likely up to 7 or 8 on the second) who have flown those simulators, have reported that the simulator performs and, critically, handles, as much like the airplane (the B-737) throughout the aerodynamic stall entry, the actual stall, and the stall recovery, as any anything they have seen. As an example of the competency of these pilots, one that I witnessed personally, when an interested observer quizzed one of these test pilots how far he had personally taken that airplane into the actual aerodynamic stall … he answered, “a 3-turn spin.”
This Thread; June 7, 2014 @ 19:23; Post#42
The 2 specific B-737s to which I referred in that post were, first, the B-737 located at the FAA’s Aeronautical Center in Oklahoma City, OK, and the second one is a B-737 located at the training facilities of Boeing in Seattle, WA. When I described the answer provided by one of the test pilots, during his demonstration of the simulator’s presentation of the stall and stall recovery when asked how much experience he had with stalling the B-737 and his response was “…a 3-turn spin…” that person was a former Boeing test pilot who, at that time, was an instructor/check airman at American Airlines, assisting on the development of the aerodata package incorporated into the B-737 simulator at the FAA Academy.

Simply because I haven’t been personally involved with this particular effort in quite a while now, I cannot be sure, but I would be more than a little surprised if I were to learn that the Boeing B-737 simulator in Seattle, having exactly the same goal as that of the simulator at the FAA Academy, having been flown regularly by the Boeing technical staff, including test pilots, has not been “flown” personally by Captain Wainwright. As I indicated in that post, these 2 simulators are currently (or were, at my last understanding) programmed with a wholly new aerodynamic program (and not the same program) generated under a whole list of parameters to help assure that the result would provide aerodynamic response and “input cueing” to the pilots aboard, that are substantially more realistic in that portion of the flight envelope that is AT and BEYOND the traditional normal flight envelope boundaries. Significantly, with the involvement of anyone associated with such an effort, particularly if they report to someone like Captain Wainwright, I would be more than a little surprised if any release of such an aero-data program for training on stall/approach to stall recognition and recovery would be allowed if there were any significant hesitancies or concerns - unless, of course, there were adequate limitations and admonitions that accompanied such a release.

As I’ve said, and I think has been said by others here, a simulator is NOT an airplane. It is bolted firmly to the floor; it can provide definitive motion input cueing only through, and to, the limits of that motion system, with a limited magnitude envelope; can provide additional input cueing of both the simulator’s sound and visual systems and through the instrument displays. The key is to be able to provide input cues that are as close to the same cues that would be recognized in the airplane – and we must recognize that these cues are, and it must be understood why they are, limited to “on-set” only. For example, g-forces simply cannot be produced beyond those very briefly recognized at the on-set of the movement. As a result, anyone, particularly a pilot, is able, with relative ease, to recognize and consciously understand the inaccuracies between the airplane and the simulator. However, the simulator’s “pilot” occupants, particularly those who are, indeed, pilots, actually have the option of “playing the game;” that is, recognizing what the simulator is providing (i.e. “on-set” cueing) – which is very likely dead-on accurate at the very initiation of that cue, or, is at least accurate to within a very small deviation of what the “real” on-set cue would be.

Of course, if the occupant’s attention is focused on those differences, it merely reaffirms to that pilot, that what he/she is seeing, hearing, and feeling, is only a simulation and is not real. However, with a very minor adjustment in attitude or intent, basically a willingness to “play the game,” the simulator experience can, and often does, generate a MUCH more realistic response – to the extent that, according to some of the scientific/physiological data gathered, the pilots actually experience reactions quite similar to those experienced in the airplane, i.e., heart-rate and blood pressure increases and decreases, pupil dilation and restriction, breathing rate alterations, etc.

The admonition I continually repeat is that the student must “FLY” the simulated airplane JUST LIKE one would fly the airplane … and at least some of the time that may require a gentle reminder by the instructor. However, this periodic instructor input has to be learned … that is, the instructor has to either recognize or be taught to recognize when a student in the simulator is “flying the simulator and not flying the airplane,” and then that instructor has to learn the best way to bring that student back to the business at hand … learning to fly the airplane, or flying the way they “know” to fly the airplane.

In order to do that, the instructor MUST know and understand the simulator’s tendencies – likely best understood by knowing how the simulator is programmed, what the limitations are in that programming, and the limitations of the simulator to replicate the actual airplane. And, that is in addition to being able to recognize an issue that I’ve only recognized in the last couple of years. This issue is that some students approach their simulator sessions armed with a whole litany of “cheat-sheet” methods to employ to assure, or at least to assist, in getting satisfactorily through the “mission” of completing the training or passing the check. Very observant simulator users are sometimes able to recognize how to “game the game,” by learning specific power settings or magnitudes/direction of control input, etc. and when and in what order those values should be employed by that student … and doing so will, at least most of the time, provide at least an acceptable presentation to an instructor or check airman who doesn’t recognize the use of such pre-determined values.

In case you haven’t guessed … I am a huge proponent of simulation … but I hasten to had that my support is specifically focused on the accuracy of the simulation (to the greatest extent possible); the abilities of the instructor/evaluator to know and apply the limitations of the specific simulator being used; and the student’s focus being on “flying the airplane” and forgetting (as much as possible) that he/she is actually in a simulator.

Last edited by AirRabbit; 3rd Jul 2014 at 19:54.
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Old 4th Jul 2014, 03:08
  #93 (permalink)  
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Bergerie1

To address your first post. I would totally concur with your comments with regards large jet transports. The particular Level D FSTD I referred to represents a large regional turboprop that does have surprisingly good aero data within this region.

Additionally we are fortunate to have a Chief Pilot who was a test pilot for the airframe manufacturer and who has on numerous occasions performed this manoeuvre on the aircraft. He confirms that the approach to stall, stall and (most importantly) the stall recovery technique is very accurately represented on this FSTD. (It is for this reason the he has incorporated the demonstration of this within the type rating program).

Your second post raises a multitude of issues. Whilst not for 1 second would I dispute the accuracy of what you stated, I do think that at times the major airframe manufacturers are somewhat too dictatorial and maybe too conservative.

e.g. Airbus repeatedly state that “training should stop at the stall warning” yet (EASA) regulations clearly state that FSTDs should be tested both objectively and subjectively up to the point of stall. Additionally, many of our airline users also want to train their crews beyond the “Stall Stall” but the current data beyond this point is somewhat lacking and certainly unrepresentative.

Better and more accurate data does already exist now, both the large airframe manufacturers have stated this at conference, however the manufacturing ‘industry’ is quite content to provide the minimum to satisfy their perception of what is adequate to (just) meet regulations and adequate for their perception of normal training needs.

I would suggest the recent experience has shown that something more than their perception of normal training may well be required to ensure safe flight?

Data (to the operator) is not cheap. With initial costs starting from US2M upwards per FSTD and with literally hundreds of datapacks being sold over the typical life of a major airframe there really is really no excuse from the major manufacturers not to invest more effort into what is the heart of an FSTD.

I still firmly believe that this is a regulatory responsibility to fully enforce current regulations and to find a better way to fast track required changes. At least the FAA has shown some initiative with their new requirements for stall recovery and bounced landings training etc, but 5 years!
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Old 4th Jul 2014, 09:53
  #94 (permalink)  
 
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AirRabbit,
Thank you for your detailed reply, I also, am a devotee of simulators and find them fascinating machines. I also fully agree with your comments on 'onset' cues and the need to fly the simulator as one would the real aircraft. I note with interest your statements about the 737 simulators that have improved data that replicates the aircraft's behaviour post stall.

ZFT,
Thank you for your reply too. You are lucky to have a company pilot with the knowledge to extend the scope of your simulator's data into the post stall regime. I also take your point about the airframe manufacturers' not providing the additional data.

But this leads to three questions which I would like to put to both of you:-
1. I wonder whether instructors throughout the airline community are taught enough about the limitations of simulators. Are there still people out there who train inappropriately in areas beyond the flight envelope that has been programmed into their particular simulator?
2. Is the industry doing enough to address the above issue?
3. Do we really need to spend the additional money to acquire test data in these extreme areas? Or would it be better to concentrate on teaching a greater understanding of the aerodynamic and control principles instead?

I know this discussion is deviating from the original one on cross-wind training. Nevertheless, it has relevance in this area too, since flight data in ground effect is a very complicated area. Perhaps this may be one of the reasons why contributors to this thread have experienced a lack or realism during cross-wind landing training.
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Old 4th Jul 2014, 22:04
  #95 (permalink)  
ZFT
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Bergerie1

A quick response for now.

I wonder whether instructors throughout the airline community are taught enough about the limitations of simulators. Are there still people out there who train inappropriately in areas beyond the flight envelope that has been programmed into their particular simulator?
Really 2 questions. Are instructors taught enough about limitations? Undoubtabley no but this issue is not as significant on the latest generation of FSTDs where the instructor and trainee can expect and should demand to experience 100% fidelity with systems and performance and a very high degree of fidelity in all ‘normal’ manoeuvres within the obvious limitations of the device. Within this thread we are really only debating the exceptions, albeit highly important ones.

I also do not think there is a significant issue with instructors using FSTDs outside their designed and/or qualified envelope. The issue I believe is more that (some of) the qualified FSTDs don’t subjectively perform appropriately in areas within their flight envelope!!

I am in total admiration of the trainers and their abilities to utilise these tools in the way that they do, sometimes with very limited knowledge of the specific device.

2. Is the industry doing enough to address the above issue?
I’m not sure what ‘the Industry’ can do about how trainers use the FSTDs (other than make the IOS operation as simplistic and intuitive as possible). This is more an operator/user issue. I would hope that a good CMS and equally good HoT would ensure correct and appropriate usage?

3. Do we really need to spend the additional money to acquire test data in these extreme areas? Or would it be better to concentrate on teaching a greater understanding of the aerodynamic and control principles instead?
I don’t believe that any significant expenditure is needed. Most, if not all of the raw flight data already exists. It just needs to be processed and made available.

As to whether it would be better to concentrate resources as you suggest – I will leave that response to those far more qualified to give their views.

Last edited by ZFT; 4th Jul 2014 at 22:16.
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Old 5th Jul 2014, 01:16
  #96 (permalink)  
 
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Regarding flight testing and data gathering, I think it's pertinent to point out that Capt. Wainwright's paper was published back in 1999, and while he is absolutely correct in what he says, recent events have caused something of a shift in how both Boeing and Airbus approach stall testing:


AF447 and similar incidents have effectively proven that in certain circumstances, teaching "approach to stall" simply isn't enough. And while simulators will not be able to mimic the real aircraft's behaviour entirely, I can't help but think that instilling a general feel for the process of stall recovery at least can't hurt.
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Old 5th Jul 2014, 01:23
  #97 (permalink)  
 
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Hi Bergerie1

Originally Posted by Bergerie1
I wonder whether instructors throughout the airline community are taught enough about the limitations of simulators. Are there still people out there who train inappropriately in areas beyond the flight envelope that has been programmed into their particular simulator?
First ... I'm not at all sure if everyone using a simulator is aware of what that simulator can and cannot do. To many, "if it happens in the simulator - THAT is what you can expect in the airplane." That is likely because someone, someplace, said that same thing - or something similar - and they have not yet seen (or at least recognized) anything to counter that understanding. I am quite sure that most simulator instructors would likely say that they are adequately trained – but my concern is that many (and only because it smacks of an insult do I not say “most”) are not fully informed about what the limitations are, and even those who do have some knowledge about some limitations, they likely have not been instructed on how they, as instructors, should deal with those issues … and I say this because simply acknowledging something like “…oh, don’t pay attention to that … that’s not the way the airplane does it ….” just doesn’t address the gap that now exists in the mind of that (those) student(s). However, like I indicated in my earlier post, there is now underway several individual efforts – some of which directly address the competencies of pilots, instructors, and evaluators.

Many instructors teach what they, themselves, were taught, and teach the way they, themselves, were taught. Most instructors are likely to have not taken the time to understand what it is they are teaching and what they are likely to see, and, from that make appropriate modifications to what it is they should teach and what it is they should expect. Interestingly, many of them might have a problem in explaining "why" they expect what they expect - other than "that's what the syllabus calls for."

For your information and your consideration, the Annual International Flight Crew Training Conference, a “premier” event in the Royal Aeronautical Society’s annual calendar is scheduled for Tuesday, the 23rd, Wednesday, the 24th, and Thursday, the 25th of September at the Society’s Headquarters in London. The plan is to examine the work undertaken by the International Pilot Training Consortium (IPTC) with a view toward seeking to determine what further work is required and under what auspices it should be conducted.
Originally Posted by Bergerie1
Is the industry doing enough to address the above issue?
Ouch – I guess the proper response here is “how much is enough?” Realistically, there is an on-going effort (see above) … which, in itself, says volumes to those of us who have been IN this industry for more than a little while. Will it be enough? That is yet to be seen. One good way to find out, would be to attend the conference and ask that same question.
Originally Posted by Bergerie1
Do we really need to spend the additional money to acquire test data in these extreme areas? Or would it be better to concentrate on teaching a greater understanding of the aerodynamic and control principles instead?
I’m not sure how to answer this question because as of now there are two aero-programs that are reported to be quite good in the stall / post stall portion of flight. It’s my opinion that the remainder of the flight envelope is pretty well addressed with appropriate data at the moment. Of course, there are a full range of simulators in operation at this time – and collectively they represent the full history of data gathering, reduction, modification, and incorporation into simulation. Unfortunately, not everyone who has flown an airplane simulator, has good experiences – and often it’s not the simulator’s fault. In some cases, at least, the simulator is used inappropriately or incorrectly.

The result, at least at some level, can be interpreted as the simulator being the target of the “negative” comments. In the cases I’ve seen personally, which is a substantial amount by most measurements, a huge portion of the reasoning lies directly at the feet of the individual students – primarily because of they are trying to “fly the simulator” instead of flying the airplane. That may sound “weird” to some degree – but I promise, there is more truth in that comment than there is “weirdness.” Overall, in those cases where it is clearly not the student or the instructor, I say for the most part, the “jury is still out” – as to whether or not the “fault” lies with the simulator itself – and I say that because sometimes the persons making the accusations don’t really know why they feel as they do.

A lot of folks do not know what data is collected, where it is collected, and how it is collected; nor do they understand where and how it is used in the simulation of an airplane. I really think most would be quite surprised if they were to read just what kinds of data are required, how that data is actually gathered, and how much work goes into converting all those numbers into a legitimate aerodynamic program. For those interested, I’d suggest checking the internet for the FAA’s regulations on simulators: It’s found at Title 14 of the Code of Federal Regulations, part 60. Once there Appendix A addresses airplane flight simulators – and to really understand what is included, it’s necessary to read the WHOLE appendix – (sorry, but, it’s true).

Here's a link - eCFR ? Code of Federal Regulations

Do we really need to get the data for these “extreme areas?” I say, yes – primarily because the simulator is going to be put into those situations ... by error or on purpose, whether or not the person(s) in the simulator actually intended to get to and/or beyond those boundaries. And, because it IS a simulator, a lot of folks will take with them at least some aspect of what they saw, heard, and/or felt … whether or not the simulator was accurate or only partially so. Besides, it has always been a desire that students understand what an aerodynamic stall is, how to recognize it, and most importantly, what to do to recover the airplane to a safe flight condition. Without the accuracies provided by accurate data and programming … I think we’re still “whistling in the dark.” Besides, I'm of the opinion that there will always be a better, more accurate, more detailed, less expensive, etc. etc., manner found to collect the data and a better, more accurate, more detailed, less expensive, etc. etc., method of reducing that data into a useable simulator program. Someone once asked me if I knew how expensive training really was to an airline ... my answer (admittedly taken from an older and much more experienced aviator than I) was "...not really, but I'd bet it would be less than an accident."

Also, you might want to check that same document I referenced above to check on how the FAA, at least, deals with crosswinds, specifically how the data is gathered for that specific portion of the simulator’s programming.

Last edited by AirRabbit; 11th Jul 2014 at 03:24.
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Old 6th Jul 2014, 08:39
  #98 (permalink)  
 
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Whilst I don't have anything like the training or simulation experience of some of the very erudite posters on this thread, I have just finished a type rating on a completely new type and size of aircraft (a smallish bizjet) in UK CAA approved Level D sim, followed by flying the aircraft itself and have some observations on sim fidelity.

The simulator was very bad at simulating the aircraft behaviour below about 100ft. The ground handling was very over-sensitive, with PIO being very easy to induce on the takeoff or landing rolls. The landing behaviour, especially in crosswinds, bore little resemblance to the real aircraft (which is the easiest to land I've yet flown). This was mainly down to the modelling of the control loading. The aircraft in question uses direct cable controls - I imagine it's harder to model actual aerodynamic loads than the various artificial feel systems in aircraft with hydraulically assisted flight controls?

Separately, I have read a few articles in Flight of late about Lm2 lateral acceleration modelling which seems to make handling exercises seem significantly more realistic - can anyone tell me what it is and how it works?
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Old 6th Jul 2014, 09:09
  #99 (permalink)  
 
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Hi Jwscud,

About Lm2 | AWx - Acceleration Worx

You are not alone. We must use our sense of lateral acceleration (poor in most sims) and heading changes (non existent in most sims) to anticipate track deviations earlier. When those clues are missing or lag the real world, then we tend to over correct which causes PIO.

& I'm glad this effect is now admitted:
"Many pilots also develop nausea in simulators due to the poor correlation between visual and motion cues."

Lateral thinking for simulators - Learmount

http://www.flightglobal.com/news/art...-their-325612/
"This is because pilots have been taught to rely on their eyes to judge aircraft performance, and whereas in a modern FFS the visual systems faithfully represent a real world perspective - as do the aircraft instruments - the motion systems cannot represent real-world sustained accelerations and the sensations associated with sustained attitude change.

Motion systems can only represent the onset of a physical cue, such as vertical or lateral acceleration, pitching or rolling, but then they have to bleed it off, which provides human physiology with a feeling of acceleration in the opposite direction. The latter sensation tends to lead to pilot induced oscillation, and if, during long simulator training sessions, a pilot's handling performance improves, it tends to be because he/she is becoming an expert at "flying" the simulator, which is not the same as flying the aircraft. This is a description of a phenomenon that rings true in most professional pilots' experience."

http://www.flightglobal.com/news/art...kc-135-400950/
"Lm2 is a patented software solution that modifies the conventional lateral accelerations applied by six-axis motion systems in full flight simulators – which frequently cause trainees to overreact, resulting in pilot-induced oscillations."

Last edited by rudderrudderrat; 7th Jul 2014 at 11:39.
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Old 7th Jul 2014, 20:01
  #100 (permalink)  
 
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As I’ve said regularly here, in my sordid past I’ve had the pleasure of working with some of the brightest and best thinkers in this industry – why they allowed me to be regular part of their business may be open for a lot of heavy criticism or ridicule, but that is a story/discussion for a later time. Because this LM2 issue seems to be provocative, I’ve talked with a very good friend of mine who happens to be the FAA’s Chief Scientific and Technical Advisor for Flight Simulation Systems (I hope I got that title correct) and the result of my recent conversation with him … and his providing some correction of my thinking and confirming other portions of what I thought, is contained below … and I think many (most?) of you might find the following to be of some interest.

Basically, adding the “LM2” algorithm into a simulator does several things, and probably the primary aspect is that the lateral motion cue (side-to-side movement) is considered primary. With understanding this position, the LM2 forces the lateral movement cue provided by the aero-model (determined from airplane flight testing) to be “in phase” with that model. Note, it is the “phase” of the movement that is being kept the same, not the “magnitude.” The method used to achieve this is to combine the lateral motion (left and right) of the simulator WITH the rolling motion capability of the simulator. When these motions are forced to be “in phase” the resulting lateral motion “feel” in the simulator is quite often better than it would have been previously. However, the rolling motion that is used is NOT the rolling motion of the airplane, it is the rolling motion of the simulator.

It is these 2 motions that are essentially forced to be "in phase." At the same time, this additional LM2 programming also adjusts the rolling movement when the pilot inputs a control wheel movement (either left or right) so that a spurious, or false, side-force in the lateral (side-to-side) direction is not generated – which, by itself, is probably a good thing. However, this is achieved by limiting the roll capability of the simulator, resulting in a situation where the simulator cab cannot roll much to represent the aircraft's roll, effectively decreasing roll fidelity – and, some would say, critically decreasing that fidelity, meaning that the potential for experiencing a false roll cue has been increased.

Of course, there are some who would say that there is a darn good reason for having “good lateral cueing.” Certainly, I don’t argue with that premise. However, providing this “good lateral cueing” is accompanied with both, the lessening of the quality of roll cueing and establishing a potential for introducing a false roll cue.

It might be interesting to know that according to the data gathered by a myriad of research involving flight simulation there is an understanding that it isn’t absolutely necessary for the lateral cueing of the airplane and the lateral cueing of the simulator to be exactly at the identical phase (again, we’ve never attempted to match magnitudes - the size and actual movement of the simulator would be prohibitive). This research, I’m told, indicates several things:
1) These two motion values can be as much as 30 degrees out of phase and still be providing a good cue;
2) There is nothing wrong with having some side-force due to roll. In fact, the indications are that up to 0.05g's is acceptable before that lateral movement begins to infringe on the rolling cue recognition by the simulator occupants - primarily the pilots;
3) At the same time, rolling the simulator to produce a good lateral (side-to-side) cue such as is provided by this LM2 algorithm can make the occupants “feel” that the cab is rolling in addition to moving laterally, which would be at least confusing. (Note: a typical person will feel the cab rolling when it is rolling at 2 degrees/second or more); and
4) “Over filtering” the roll cue can, and usually does, provide poor roll cueing, and the method the LM2 algorithm uses to increase lateral fidelity, actually reduces the roll fidelity.

There shouldn’t have to be an “either/or” decision that has to be made. The fact is that “the best of both worlds” can be achieved by using the algorithms typically installed in simulators today by improving the lateral cueing at the expense of the roll cueing … but that does not mean that one should have to go as far as what LM2 does.

I understand, and it has now been confirmed, that some time ago there was a petition filed with the US FAA to add a requirement to include the LM2 approach to the US Simulator Qualification Regulations. This was carefully reviewed and the conclusion was that as long as adding LM2 into the programming of a modern simulator did not negatively affect the required objective testing results and did not negatively affect the required subjective test results, the FAA would not object to its being included as a part of the simulator’s programming … but the FAA also decided that they would not require that LM2 be incorporated into any simulator.

Finally, and according to all the available data and professional and objective analysis, what LM2 provides, is probably somewhat better than where most folks are today, but logically, the question should be one of finding the “happy medium” and not necessarily compromising one cue for providing an increase for another cue. After all, we are attempting to make the simulator as “real” as possible … right?
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