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Man-machine interface and anomalies

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Man-machine interface and anomalies

Old 21st May 2012, 01:58
  #81 (permalink)  
 
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Originally Posted by Lyman
Out here in the west we call that "side-saddle". Only in this case, the cowboy is heading sideways

1974 Air France woman uniform : skirt, no hat, no tie
(Danièle Decuré, first woman pilot)

http://i1166.photobucket.com/albums/q601/femmes_pilotes/decureenjupeAF.jpg
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Old 12th Jun 2012, 18:17
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Has anybody some information about
1. A330 feedback equations including speed parameter V ? and information about A330 cross-over velocity Vco?
C* =? Knz.nz + Kq.q and is it standard C* ?
2. relative position of the accelerometer ? in normal flight and stalling deeply,
3. where does the "speed" input in the feedback come from in the UAS case?

Thank you
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Old 13th Jun 2012, 03:32
  #83 (permalink)  
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Hi roulishollandais,

Please provide more details on your questions.


Still very busy, unfortunately with no spare time.
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Old 14th Jun 2012, 17:52
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The Drill...then

The Drill for me as F/O, after having assisted my Captain with the Ditching, required me to go through the passenger cabin to the rear passenger door...

("Please stay in your places and let me through..." to each of the 100+ SLF)

I was to take a large Dinghy, put it through the door, inflate it and float it to the port wing, so that passengers from the port escapes could embark. I then was required to take the second Dinghy, inflate that and board it, paddle it myself around the tailplane to the starboard wing, so that the rest of the passengers could embark.

This would be easier to do, I think,
(a) by daylight,
(b) with a flat calm sea
(c) without ANY wind

We never practiced this on training... too expensive on aircraft, but we had a good write up from another airline using the same type of aircraft who said that "they were good at it because they practiced"!

(How shameful to be seen paddling away in the second dinghy just as a gust of wind sprung up taking the dinghy and me out of sight... Today, this would all have been recorded on passengers' mobile telephones !)

Last edited by Linktrained; 14th Jun 2012 at 17:58.
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Old 3rd Jul 2012, 15:45
  #85 (permalink)  
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AF447

Hi,

BEA final report in two days.

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Old 22nd Jul 2012, 07:26
  #86 (permalink)  
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Decent man machine interface

Hi,

What can be done (should be ASAP) to avoid another case?
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Old 8th Oct 2012, 23:22
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The Drill then... Pt2

Our Acting Chief Pilot understood the F/O's post Ditching Drill would be impractical for the reasons that were put (above).
(Some years earlier he had successfully ditched an aircraft himself. Practical experience was valuable.)
The role of "dinghy thrower outer" was given to the No.1 Steward.
If I survived, I was to put my hat on. (It sounds daft but it would give me identifiable Authority in the confusion)
Then I was to help...
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Old 9th Oct 2012, 18:15
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Thank you Linktrained, to dedramatize our discussions !

Us, French and Americans shall ask our both new Physik Nobel Price in mesurement and quantification of mécanique quantique if they have a solution (or many !)
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Old 9th Oct 2012, 19:10
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Mode confusion is intrinsic in highly automated systems. It is incumbent on the system to clearly communicate why the mode has changed and the implications.

Dropping the AP and a console alarm announcing "Unreliable airspeed" won't do, particularly with pilots who do very little hand/raw data flying.

"Hi guys! Sorry to disturb you but my pitot tubes are not giving me a reliable airspeed. I have disconnected the autopilot and we are now in alternate law"

"I suggest that you turn off the FD and just fly pitch and power while see if I can get our airspeed indications back."


Result (probably), no panic stickback, no stall and no accident.

Mac (the other Mac, not a pilot but has programmed an automated system)

[Never mind the non-coupled sidesticks, the autotrim and all the rest of it]
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Old 9th Oct 2012, 19:33
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Watching these threads is like watching TV at 3 o'clock in the morning. You know it is going to be nothing but re-runs of stuff you've seen many times before. It does give you the benefit of being able to switch off for weeks at a time knowing that nothing have been missed, which is something I suppose.
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Old 11th Oct 2012, 01:36
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roulishollandais #88

Nobel prize... In the last couple of hours Reuters has reported a Study showing a correlation between a nation's per capita chocolate consumption and Nobel prize winners. This is reported in " The New England Journal of Medicine". It MUST be true !

Some may have missed the obituary of Mrs. Evelyn Johnson who died aged 102. She had logged 57,635 hours, mainly as a flying instructor, continuing to teach until she was 96, latterly with a prosthesis, following a car accident. This she said "made it difficult to get into small planes !"
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Old 12th Oct 2012, 19:19
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I will disconnect the AP/AT and go to alternate law

Completely feasible long time ago to:

1) Inform assertively on the limitations being faced

2) Orient crew clearly on proper procedure

Simple, like Leonardo Da Vinci stated:

"Simplicity is the ultimate sophistication"

There are other possible ways to design...K.I.C.S.

A pilot in the high rocks of the R&D Dept. would generate better design.
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Old 12th Oct 2012, 19:55
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Do we know everything that occurred that night?

Clearly there are unsolved questions. When working in so exciting issues we need to be open minded like we need when driving a machine that can always present surprises. An a/c is female, so surprises present challenges to us.

Probably the focus should be the "interface" which IMhO created "HF issues".

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Old 13th Oct 2012, 01:06
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Originally Posted by RR_NDB View Post

A pilot in the high rocks of the R&D Dept. would generate better design.
Pilots were extensively involved in the design. Gordon Corps in particular - and at a very high level. There is ample evidence of this in articles, interviews and videos from the time, many available on the net if you choose to look.

He (& other pilots) were involved in design and flight testing of the control system using modified A300 test bed prior to A320 build. In fact, aspects of the control system were changed significantly following the A300 flight tests - that was on pilot feedback. I presume I don't need to detail the major change that is rather relevant to this thread, since you "know" the history of design and who was involved ?


As to the end result - you may not like the decisions those pilots made, but that is as far as it goes. You are entitled to that opinion, but that does not mean that those pilots were not there, or that they were not "real" pilots because they disagreed with you (maybe that is what you are trying to infer ?).
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Old 13th Oct 2012, 07:48
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Could you tell me why?

Obviously, this was necessary for many reasons. Their influence in the design seems as secondary. The IT, automation, etc. seems prevailed. The new concept certainly gone beyond some existing "thresholds". The new concepts appear simply not enough developed to possible scenarios when things go south. AF447 perhaps the best example of this.

The "threshold effect" (AM x FM, S/N ratio analogy) when plane degrades could create dangerous situations even for a designer flying the A/C. Airbus SAS philosophy seems adequate up to a certain threshold of problems.

Above a given threshold i heard important observations from experienced pilots that flew equivalent A/C.

The LOC after a System limitation imho should be addressed very seriously. HF seems to me a result from serious issues in the "interface" design.

I am motivated to address deeper some facts in this thread.

Could you tell me why not:

1) Inform assertively on the limitations being faced by the System

2) Orient crew clearly on proper procedure wrt to easily detectable UAS
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Old 13th Oct 2012, 12:42
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Not Green, Gray...

I am reasonably convinced that the lack of Pilot/Pilot interface engineered into the Airbus cockpit was not arrogance , nor ignorance.

The dynamic, ignored in the lack of interconnectivity with hand controls, shows a confidence in the human factor that has created problems in flight. The knock on the platform early on, "What's it doing now....?" has in some instances been replaced by "What are you doing now...?"

The design clearly shows a lack of attention to this dynamic factor, cockpit management. It certainly reflects on a lack of concern for the importance of either handling position relative to controller orientation, aircraft attitude.

And in fact, the sidestick is not always reflective of a direct positional relationship stick/aircraft. The geometry has at least two modes: first, the angle of the stick whilst held, and second, the short loiter at a random point in its arc driven by a human input that is not quantifiable due to its short duration. In the second instance, the target angle is a "best guess" and subject to additional refinements in subsequent "hunting" by the handling pilot. This has unfortunately been termed "stirring mayonnaise". Since this motion is guesswork by the handler, it is likewise guesswork for the non handling pilot, should he be interested in its travels.

Both sticks are active, ordinarily, and if unarticulated, rest in neutral. If a handling pilot is putting in an angle that is detrimental to the flight path, his opposite cannot know by seeing his own non moving stick. He can see the instruments, but in turbulence, or in rare occasions when instruments are unavailable or inaccurate, he relies on the flying pilot to manipulate his stick correctly.

In the even rarer circumstance when a pilot is mishandling, there is a problem.
The monitoring pilot must stop what his tasks are, and enter a zone of diminished interface, "what is he doing?" "you go up, so go down...."

"Are you pulling?" "if you are pulling, stop pulling..." "stop, STOP". These are comments based on conjecture, for the monitoring pilot has no awareness of the flying pilot's stickwork. Then, "My Airplane"... If the taking of control is based on an error in assessing, guessing, the other pilot's stick movements, the stage is set for confrontation, or a dangerous interruption of control in what may have been a mechanical problem, or weather, not mishandling....

So our non flying pilot can be put in the position of confusion; does he doubt the instruments (there were problems with one or two, perhaps airspeed, or flight director mode). Or does he put his faith in the panel, and his senses of attitude, and take control?

In this gray area when the second pilot senses something wrong, he may err on the side of continued mishandling, or take over from a pilot who is doing a proper job. In certain rare circumstances, and in emergencies, either course of action would be wrong, and possibly fatal.

It has been noted by a respected authority that the lack of visibility one stick to either pilot is notable; I have added some possible reasons why it might be dangerous? This same potential would also apply to a lack of interconnectivity.

Last edited by Lyman; 13th Oct 2012 at 15:00.
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Old 13th Oct 2012, 18:45
  #97 (permalink)  
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Artificial training

Your simple and direct comment motivated me to remember how rich is the "management" of a complex task when the variables are natural. For example, WX issues, varying atmospheric conditions, energy management issues, speed calibration, surface contact management, etc.

This is fascinating in planes, high speed cars, bikes, etc.

When you are dealing with "threats" and "traps" created by designers together the dynamic nature of vehicles you are in a very different challenge. Absolutely "non natural".

The need for the pilots to remember (after training) the logic implemented by non pilot designers simultaneously with natural adverse conditions, creates a formidable challenge.

And the operator of the machine you commented above is clearly a "poor" equipped guy. Very limited. This trend is indeed concerning.

IMHO there is a need for a balance in the automation specially in the interface to allow the supreme commander to exercise his very best expertise when required.

In the limit would be better to eliminate the crew...

Perhaps the crew is being attacked since the advent of Intel 4004 by "non pilot" designers.

The interface specially during anomalies MUST be very natural, intuitive.
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Old 13th Oct 2012, 19:34
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Not Green, Gray...

This poses another set of variables to the always required good CRM. During transients and anomalies (System limitations, etc.) the threat is serious and the stakes could be high.

F-GZCP was doomed in the transient after a System anomaly. Just HF could be adequate to avoid another case? That can be more complex and brief.

Last edited by Jetdriver; 16th Oct 2012 at 15:38.
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Old 13th Oct 2012, 19:47
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Hi RR_NDB

Yes. I don't think the problem of confusion can be overstated, here. There were two pilots on board this aircraft who, for 30 seconds, at least, had an extremely compromised situational awareness.

From the data, the pilots were not immediately aware of the status of autoflight, save for grasping one of the SideSticks....nor were they aware of the Controls Law that had occurred via degradation of actual data. This we know, for no mention of degraded Law until seventeen seconds after the loss of autopilot and NORMAL LAW.

The utter lack of any pre-prepared drill applied by these two crew is evidence of a complete breakdown in anticipatory planning.....

Pilot problem? Hmmm.......One immediately thinks of a programmed and annunciated sequential deletion of services, and its absence on the flight deck....

IOW..... "GoodBye". Instead, ALARMS.... INTUITIVE? NOT........
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Old 14th Oct 2012, 23:48
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Originally Posted by Lyman View Post
I am reasonably convinced that the lack of Pilot/Pilot interface engineered into the Airbus cockpit was not arrogance , nor ignorance.

The dynamic, ignored in the lack of interconnectivity with hand controls, shows a confidence in the human factor that has created problems in flight. The knock on the platform early on, "What's it doing now....?" has in some instances been replaced by "What are you doing now...?"

The design clearly shows a lack of attention to this dynamic factor, cockpit management. It certainly reflects on a lack of concern for the importance of either handling position relative to controller orientation, aircraft attitude.
It is worth reading and watching what information there is from the time from the pilots involved in the design. I only did so recently, it opened my
eyes a bit to the aims of the design beyond the engineering.

Not only is it clear that they did pay attention to exactly what you say they didn't, but they also rejected the first sidestick design after flight test (not sim, flight) and sent it back to the engineers not for a bit of tweaking but for radical design changes.

Do you know what they scrapped, at flight test, and rejected in favour of what is there today ?

... Interconnection. Yes. Really. They had interconnection and they scrapped it after test flying it. Apparently it was great in theory but didn't work when you actually tried flying it (even with test pilots). Interesting, no ?
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