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LH A320 Rough Landing @ Hamburg

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LH A320 Rough Landing @ Hamburg

Old 14th Mar 2008, 21:45
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DozyWannabe,
Historically, theZiegler quote is not the one that antagonised the French pilot population but this one :
"airline pilots ? Are they anything more than taxi drivers ?"
That in response, IIRC to a query by the SNPL (main Union) -would you believe - about moving throttles.
Then it became quite ugly.
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Old 14th Mar 2008, 22:11
  #462 (permalink)  

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Training for new Technology

As a conclusion to what we've been talking about for quite some time, I'd submit this paper by Capt John Bent, ex Cathay Pacific Training Manager.
It was written in 1994 when CPA received the new Airbuses, after a long experience with Boeing and Lockheed products. At CPA, they sensed that the whole training philosophy had to be re-thought and this is what he wrote for a CRM symposium :
Training for New Technology
It is about training philosophy, new concepts and flight safety, mainly.
John Bent later set-up with a colleague two TRTOs in order to cope with the need of new pilots for China and was involved (still is ?) with the GEcat school in Hong Kong.
If anyone could be credible on the subject, he certainly is one of them. (Chris, need your input soon on the subject, too)
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Old 14th Mar 2008, 23:24
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Lemurian - probably so. I've never heard that one myself - but the whole attitude seemed counter-productive to me, admittedly looking at it with 20-20 hindsight nearly 10 years after the fact (which was when I was at University studying Software Engineering).

But we live and learn - it's just a shame that all this negativity had a chance to take hold in the interim.
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Old 15th Mar 2008, 04:36
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Chris, if I can add some precision to your post 229

Stick-to-elevator control does not trigger the Sidestick Position Indicator (white cross) which is only visible on the ground and disappears as soon as the main L/G lifts-off.

Also the different transitions between Normal Law and Direct Law during landing and takeoff phases are more progressive. I would say it is not after 5 seconds but during 5 seconds: “The system blends in ...” in a way that’s almost unnoticeable.

That’s why I pretend Airbus could (and should !) re-introduce the Roll in Direct Law for the flare, and get rid of that undesirable roll rate.
Decrab landing would be ... classic !

Originally Posted by DozyWannabe
The training *makes* it instinctive - it's the whole point of training
I would be interested if PJ2 could publish some figures from the Flight Data Monitoring regarding “Dual input” ... That would not surprise me if “Dual input” warnings largely overshadow “Priority left or right” advisories.

A procedure which request specific training, by definition, is NOT instinctive.

If, during a flare, a sudden situation erupt and PNF, by sauvegarde, intervenes, his probable first action will be, in an instinctive way, to simply move his sidestick. Only if he’s properly trained the next move will be to push the Sidestick Takeover Pushbutton, but as we saw in the video, a lot can happen in one single sec.
Data from HAM would say a lot ... Let’s hope we’ll see them ?

Boeing didn't consider changing their flight control input method for financial, not technical reasons
WHAT !???
Money was the culprit ? ... for BOEING ?
Well ... before taking decisions for the 777 I’ve heard some B guys did properly flight test the FBW 320.
Later, for the 787 conception, Boeing widely surveyed pilots, and had many questions specifically aimed to Airbus pilots ...
... 787 will still fly with old yokes.
If they thought sidestick was the way to go, by now they would have gone for it. With present and future fuel cost I’m afraid 757 67 47 will take a rest sooner than later, FBW 737NNG should follow 787 ...

Originally Posted by Alf
A crew should not consider landing above any demonstrated value
I can see your point, but my view is that xwind has a lot to see with pilot experience, and therefore should not be restricted in a rigid way. If an airplane, a few feet over runway, in a subtle combination of limited but approved crab + low wing, is able to maintain the center line, then he lands, and if not, he just goes around.

For LH044 Wind readings (if information is reliable ...) were in the limits (Gust included)
Even the last windcheck 32G37 was OK for the demonstrated 320 limitation 33G38

There are logical restrictions regarding tailwind.
There are also restrictions regarding xwind for ETOPS alternates (planning purpose)
There are also recommendations regarding xwind on contaminated runways.
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Old 15th Mar 2008, 15:24
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By request, I have just expanded post #474 [Yesterday, 20:52] to incorporate the amendments I made yesterday to a much earlier post on sidestick handling. These amendments owe a great deal to the contributions of everyone on this topic. Please do not hesitate to criticise the new content, as you will. It would be good to reach a broad consensus here.

Quote from CONFiture:
(1) Stick-to-elevator control does not trigger the Sidestick Position Indicator (white cross) which is only visible on the ground and disappears as soon as the main L/G lifts-off.
(2) Also the different transitions between Normal Law and Direct Law during landing and takeoff phases are more progressive. I would say it is not after 5 seconds but during 5 seconds: “The system blends in ...” in a way that’s almost unnoticeable.
(3) That’s why I pretend Airbus could (and should !) re-introduce the Roll in Direct Law for the flare, and get rid of that undesirable roll rate.
Decrab landing would be ... classic !

[Unquote]

(1) Thanks for setting me straight. I trust your manuals are fresher than my memory, and have incorporated this information in my EDITED post #474 [yesterday's posting at 20;52], above.

(2) Yes, it cannot be instantaneous.

(3) Can see some theoretical logic in your argument. Would this happen at 50'R, or 30'R, perhaps, or at L/G extension? Whatever value you choose, I would not like to be the first pilot to try this on the line in windshear and a crosswind gusting to limits or beyond.
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Old 16th Mar 2008, 18:56
  #466 (permalink)  

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Conf iture :
"Stick-to-elevator control does not trigger the Sidestick Position Indicator (white cross) which is only visible on the ground and disappears as soon as the main L/G lifts-off."
Wrong. On the ground, the displacement of the white cross reflects truthfully the movement of the side-stick, in pitch as well as in roll. Part of the flight control check we perform during taxi-out.

Last edited by Lemurian; 16th Mar 2008 at 18:58. Reason: italics added
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Old 16th Mar 2008, 20:18
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When the white-cross is displayed...

Hi Lemurian,

You and CONFiture are not really in disagreement, methinks. The context of his remark (that you quoted) was that he correctly noticed that I had suggested the presence of the white cross coincides with stick-to-surface control. This, he argues, is not strictly correct; and I am prepared to take his word for it. So I've adjusted the wording of my (Edited) Posts #229 and #474 to reflect this. Perhaps you could confirm from your up-to-date FCOM?

In haste,

Chris
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Old 15th Apr 2008, 20:43
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Old 16th May 2008, 08:32
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First status report is out

http://www.bfu-web.de/nn_41542/DE/Pu...tin2008-03.pdf

Only in German so far, but some interesting graphs of the stick inputs and resulting roll in the addendum.

They were using both sticks before touchdown simultaneously. He was countering her, whenever she rolled the plane to the left.

Seconds before touchdown she commanded roll to the left, left spoiler was deployed, then she also kicked in the rudder fully to the left...

Also noteworthy: Lufthansa's internal recommended A320 max. crosswind component for manual landing is 30 kt, 3 kt less than Airbus demonstrated max. for a not contaminated runway...

The actual wind (2min. average) at the time of incident was 33 kt from 300.
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Old 16th May 2008, 19:35
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F4F, I'm not a pilot, but judging from videos like this one:

http://www.flightlevel350.com/Aircra...ideo-9689.html

what you say in post #21

Flying in blustery weather the bus is a scary beast, either you let itself to sort it out (good luck!) or you try and give some correcting inputs. Then, depending on the concerted decision of at least 3 computers you might get some form of control from your sidestick inputs... or not

Thanks Airbus, you really gave us a fantastic machine
doesn't seem entirely correct.
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Old 3rd Jan 2009, 00:26
  #471 (permalink)  
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Google leaves me thinking the official report into this hasn't yet been produced, is that right?
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Old 3rd Jan 2009, 07:15
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Incident/accident reports are published from the BFU, you can find their webpage at BFU Bundesstelle für Flugunfalluntersuchung BFU - Homepage, you can switch to english there, click on publications, incident reports and you'll get a list of published reports. However the report to that incident is apparently not published yet.

It seems further that not all reports are published in english, probably only those where one participant of the incident is not german.
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Old 6th Apr 2009, 08:56
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There is no final report on this incident, because Airbus still can´t answer the question,
why the ailerons didn´t react to both pilots full right input. (check the graph of the BFU
report at 12:33:35)

Maybe the computer was ´stuck´ in the transition between flare mode and direct law.
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Old 6th Apr 2009, 09:24
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Yokes are old. They are on their way out. Yesterday's technology. Get used to it.
You just don´t get the point. It´s not the question of yoke or joystick, it´s just what there is behind. You could build a feedback-sidestick and direct law behind. And you can build a non-feedback sidestick with 4 different laws behind (with no indication of change)
Get used to it ? Why ? Because of AI ? As far as i know there are more than one hundred airplane manufacturer, which do it another way. Perhaps they know why .
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Old 6th Apr 2009, 23:34
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Baron737,

I agree with you on your last post.
For the C serie, Bombardier is going for the sidestick but I don't know which philosophy they will apply to it ... ?
Hope they won't repeat the Airbus mistake.

I disagree on your previous post :
why the ailerons didn´t react to both pilots full right input. (check the graph of the BFU report at 12:33:35)
Ailerons did react but roll rate limitation probably did apply as well.
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Old 8th Apr 2009, 12:16
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Ailerons did react but roll rate limitation probably did apply as well.
You are right, the roll rate limitation could have been the cause as well. But the ailerons did not react as the pilots expected them to do. In such a thrilling second you expect full aileron, if you give full input. There is just no time left to think about internal flightcomputer modechanges or envelope protections and how you can counteract them. There was no time for pulling CB´s in Hamburg either
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Old 8th Apr 2009, 12:41
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cross wind maneuver at hamburg

Looking at the video I had the following comment:

the left wing sink was in my opinion the result of the combination of:
1) strong left rudder application generating a lift wings asymmetry higer on the fasted wing (the right one)
2) the wind shadows area over the Left wing caused by the interference of the Airplane body decreasing lift
3) the cross wind over limit (10 kt?)

in addition ,becasue the control jokes are not mechanically linked I suspect that both pilots were flying the same plane in different way. The controls are electronically algebra corrected by the FBW system . I'm sure that in such extreme condition "dual Imput" is not what keep the plane more stable . But this is my own comment (non pilot) I comment this becausue I do not see any right spoilers command up even in the extreme left bank position.
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Old 8th Apr 2009, 15:31
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Actually full right input on both sidesticks came up after initial damage was done.
That incident is a consequence of improper applied technique for cross wind, important rudder input but with no aileron to counteract ...
But everybody has to learn at some point.

But mainly, no way for a Pilot Monitoring to monitor what kind of input the Pilot Flying is applying on its sidestick ... and to me it is ridiculous Airbus early on took that turn !?
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Old 9th Apr 2009, 23:01
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As far as i know there are more than one hundred airplane manufacturer, which do it another way. Perhaps they know why...
OK, but probably around 95 of them don't make aircraft that are relvant to the discussion, e.g. the Husky Aviat Aircraft: The Husky A-1C, I doubt there's been many discussions on how the joystick is going to behave (or not) :-)
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Old 25th Jul 2009, 09:33
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New Theories just published in Der Spiegel

Below is a rough translation of an article that appeared in today's Der Spiegel online.

Link Landeanflug im Orkan: Ließ Computerproblem Lufthansa-Maschine beinahe verunglücken? - SPIEGEL ONLINE - Nachrichten - Wissenschaft

"Did computer problem Lufthansa plane almost crash?

In investigating the near-crash of a Lufthansa Airbus on 1st March 2008 in Hamburg, there is a surprising turn: the air accident investigators examined after SPIEGEL information the dangerous role the flight computer played in the landing during a hurricane.

Hamburg - First, it was assumed that wind alone or carelessness of the A320 pilots were the cause of the scaping of the wingtip on the runway which was captured by a hobby cameraman. "Now the matter is complex," said Johann Reuss, investigators at the Federal Bureau of Aircraft Accident Investigation (BFU) for the MIRROR.

"We obviously investigate the role of the aircraft itself has played." According to hitherto secret investigation, results showed the A320 during the hurricane landing apparently unexpected behavior.

The most likely explanation: Because of a tire briefly touching the ground, the computer shifted from the "landing mode" to the "ground mode". The latter mode limited the deflection of the aileron, much less than the pilots commanded due to the extremly gusty conditions. The computer took over and limited the aileron deflection - and the wing tip made contact with the runway.

"Such a behavior of the machine was not documented in any manual," criticized a pilot to the Spiegel - and it is still not in there, because Airbus keeps things close to their chest until the completion of the investigation. This landing could have ended in a terrible catastrophe.

For almost three seconds the computer stayed in command. Only through the decisive and courageous action by the pilot the plane, traveling at over 200 kilometers per hour, was pulled back into the air and stabilised thus preventing a crash.
"

Hmm, interesting isn't it?
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