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AF 447 Thread No. 11

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AF 447 Thread No. 11

Old 17th Jun 2013, 12:55
  #81 (permalink)  
 
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HN39 you got it just right i reckon.

Since we first started flying it has been about using the right tool for the job and knowing which one to use. e.g.

EGPWS - Pull stick to back stop and you are doing all the laws of physics will allow to avoid the terrain.

Loss of air data - Fly a sensible power an attitude, if in doubt keep what you have until PNF gets something concrete from the QRH

No rule set changes required just a knowledge about the right tool for the job as you would on any other machine.

Last edited by busTRE; 17th Jun 2013 at 13:20.
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Old 17th Jun 2013, 13:39
  #82 (permalink)  
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AZR - since you appear to be having difficulty reading and understanding posts, let me copy the NTA quote to which I referred i the hope you MIGHT understand this time:

"Its not the crew, the airlines or the training. All airlines train and all crews are trained - it is the type of training that needs to be reviewed. "

Any better?

"I'm not aware of a long list of "AB events such as 447..." Nor am I and nor did I say that. See above.

"but I fail to see how a modification to the protection system would be sensible." - me too - see above.

HN39 - same difficulty? I have passed no comment on the wisdom of "In those situations being able to pull without fear of stalling must be an asset." - I agree - so I presume I can ignore the rest of your post after you 'quoted' me?
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Old 17th Jun 2013, 14:48
  #83 (permalink)  
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Folks, can we keep the basic credo in the landing lights ? - play the ball, not the player.

This in an extremely interesting thread .. at risk of being devalued by getting into gutter tit for tat.

I would hope that censorship is not the way to go but, should that become evident, it shall occur.
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Old 17th Jun 2013, 14:54
  #84 (permalink)  
 
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BOAC

"Its not the crew, the airlines or the training. All airlines train and all crews are trained - it is the type of training that needs to be reviewed. "
Quoting it again isn't going to make it mean anything. This point says its not the training. It then goes on to wonder if its the type of training. Well, if its the wrong type of training, then it is the training. As with much of NTA's material it is self contradictory and thus meaningless. I wonder whether that is what AZR is driving at and thus not deserving of a cheap attack at his literacy.

FWIW I believe the training was faulty in the past, in that it did not address power/attitudes appropriate to high level and consequences of inappropriate handling at typical cruise altitudes. It does now in most TRTOs.

Last edited by busTRE; 17th Jun 2013 at 15:02.
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Old 17th Jun 2013, 15:06
  #85 (permalink)  
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Whilst I appreciate AZR is 'located' in France, in English, 'type of training' is a quite specific expansion of 'training'.

Parse the following?

"I am trained"

"I am properly trained"
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Old 17th Jun 2013, 15:18
  #86 (permalink)  
 
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I don't understand why you gentlemen think you do not need AOA indicators.
If there comes a time when applying simple pitch+power to get oneself out of bad air data situation in transport plane is proven to be insufficient, then we might reconsider the need for AoA gauge.

There are times when its appropriate to fly the attitude and times when it's appropriate to fly alpha.

How do I know they had no ATT info?
You have no clue. CM2 quickly and decisively brought roll oscilation under control, proving he was looking at the PFD attitude display.

speed will vary depending upon gross weight and configuration
Not just that, critical alpha on anything will vary with mach and difference is very pronounced on A330. No reliable mach - no idea how far one is from stalling. As long as one keeps attitude and power reasonable, no big deal anyway.

I do not understand the question.
Question is: why do folks season the succinct info about flight controls from FCOM with imagination running wild and consequently accuse Airbus of having dr. Jekyll and mr. Hyde kind of personality?

Forget meaningless time in the sim and trying to land on the piano keys.
No such things occurs in the real world so there is nothing to forget.

Fully held off landings seem to be a thing of the past except on 2 airlines mainly crewed by "real pilots". WHY.
It never existed in airline world because airliners are geometrically limited, with exception of DC-3 and similar.

Last edited by Clandestino; 17th Jun 2013 at 15:18.
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Old 17th Jun 2013, 15:21
  #87 (permalink)  
 
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If I am not properly trained then there is an issue with my training.
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Old 17th Jun 2013, 15:30
  #88 (permalink)  
 
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Hi BOAC.

Once again, I won't critisize the current or past training as I have no indication that it was wrong re: the flight laws and the consequences of their reversion from Normal to Alternate and/or Direct.

I was under the impression that you were advocating that laws and their reversions were somehow "too hard to learn" for (average) pilots and thus that they should be modified in one way or another.

If that was not your point, sorry for misinterpreting your previous posts. I reacted on that because AFAIK the FCOM and other training materials already were explicit on the laws reversions, and associated loss of protections. Without access to more than those materials, I will not comment on training outside of the said materials.

I certainly won't challenge your feelings on the (type of) training needed.

++
AZR
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Old 17th Jun 2013, 15:49
  #89 (permalink)  
 
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Originally Posted by BOAC
I presume I can ignore the rest of your post after you 'quoted' me?
Please allow me to rephrase the point of my post that you seem to have missed. The single 'rule of flying' that I see is that in general you should not rely on the protections because they may not always be present. However, there a a few very specific conditions where it is appropriate to put aside any doubt about the integrity of those protections.

Last edited by HazelNuts39; 17th Jun 2013 at 15:50.
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Old 17th Jun 2013, 16:05
  #90 (permalink)  
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Originally Posted by AZR
I was under the impression that you were advocating that laws and their reversions were somehow "too hard to learn" for (average) pilots and thus that they should be modified in one way or another.
- not quite. I was suggesting that just as 'mode confusion' is a well-established derivative of our automotive cockpit, so reversionary modes could be causing confusion when infrequently experienced, and then only when things have 'gone wrong' and commonly (outside the sim) with genuine 'startle factor'.

In terms of a 'modification' I would not really know where to start. I suggested a long time ago (PGF) that from my point of view (non-AB) I would have preferred a drop straight into 'Direct' where you know you simply have a basic aeroplane in your hands which, it is hoped, one can fly. Thus none of the (eg) 'divergence' of roll law from pitch law which I understand happens as the laws degrade - all or nothing for me.

Originally Posted by HN39
The single 'rule of flying' that I see is that in general you should not rely on the protections because they may not always be present.
- so we are back almost full circle. Was the 447 PF 'relying' on some electronic guardian angel to look after him while he (following the FD?), zoom climbed and then tried to keep the nose up? If so, that is the boil that needs lancing.
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Old 17th Jun 2013, 16:43
  #91 (permalink)  
 
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Originally Posted by BOAC
Was the 447 PF 'relying' on some electronic guardian angel to look after him while he (following the FD?), zoom climbed and then tried to keep the nose up?
As a non-pilot engineer I'm reluctant to speculate on a pilot's forum about what might have been going on in the 447 PF's mind. I just can't see any reason for him to zoom-climb to seek the limit of envelope protection.

I've no experience with FD's but note that they were mostly unavailable in the first 40 seconds of the zoom-climb, and locked on to 6000 fpm V/S then 1400 fpm only after the pilot commanded those RoC's apparently independently of the FD's.
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Old 17th Jun 2013, 18:11
  #92 (permalink)  
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Assuming you have 'finished'? -
Originally Posted by NTA
All we need now is a standby altimeter that is working
- why? We believe, do we not, that all altimeters were functioning normally?
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Old 17th Jun 2013, 18:12
  #93 (permalink)  
 
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Originally Posted by BOAC View Post
- not quite. I was suggesting that just as 'mode confusion' is a well-established derivative of our automotive cockpit, so reversionary modes could be causing confusion when infrequently experienced, and then only when things have 'gone wrong' and commonly (outside the sim) with genuine 'startle factor'.
OK, thanks for clarifying that for me. I agree that a law reversion is "something more" to take into account for the crew, but I believe that the advantages of normal+alternate+direct laws are more important than the disadvantages (including the quite possible but not proven 'mode confusion').

Originally Posted by BOAC View Post
In terms of a 'modification' I would not really know where to start. I suggested a long time ago (PGF) that from my point of view (non-AB) I would have preferred a drop straight into 'Direct' where you know you simply have a basic aeroplane in your hands which, it is hoped, one can fly. Thus none of the (eg) 'divergence' of roll law from pitch law which I understand happens as the laws degrade - all or nothing for me.
I understand your PoV here, but I disagree. I have no personal qualifications necessary to defend "my" point of view, so I'll just quote two of the reasons that have brought me there:
- The existence of alternate laws comes from Airbus studies, so it is a conscious and maturely weighed decision (until proven otherwise).
- We do have exemple where the alternate law was appreciated: I mentioned the book "QF32" written by the Captain (and PIC) of this flight, but for those who do not have a copy, you can read the interview with Captain David Evans (Senior Check Captain at Qantas), who was onboard too. Both have experience on Boeing and Airbus types. Here is a short excerpt:
ASChan: Whatís your opinion of the A380ís survivability compared to other types you have flown?

DE: Well I think the Airbus A380 Ė itís a testament to the aircraft that we managed to get the aeroplane successfully on to the ground. The fly-by-wire system, albeit with the damage we were in an alternate law, it still was very flyable. Now comparing that to other types I have flown I am sure that Boeing types would have been equally flyable, but they would have been a lot more difficult, Iím sure.
The complete interview is available on a blog hosted by the Royal Aeronautical Society here:
EXCLUSIVE - Qantas QF32 flight from the cockpit | Aerospace | The Royal Aeronautical Society
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Old 17th Jun 2013, 18:24
  #94 (permalink)  
 
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Originally Posted by BOAC
I was suggesting that just as 'mode confusion' is a well-established derivative of our automotive cockpit, so reversionary modes could be causing confusion when infrequently experienced, and then only when things have 'gone wrong' and commonly (outside the sim) with genuine 'startle factor'.
Now I get it! Mode confusion refers to autoflight, not flight controls system. While modern Georges are far cry from altitude holding autopilots of 80 years ago and nowadays we're blessed with such a fine modes as HDG, WINGS LVL, LNAV, VNAV, FLCH, VOR APP, FPA etc. which provide fertile ground for confusion, there is no equivalent of such different behaviour in Airbus FCS. As long as you are flying, have flight controls continuity and are not stalled, left sticks rolls you left and pull on the sticks gets the nose up, no matter which mode you are in. Instead of trying to memorize the formulas from FCOM for subsequent interpretation, it would be easier to to think about different modes in following terms: normal - aeroplane is flightpath stable (which means pitch stable if you don't vary the speed) and will prevent overspeed, stall and excessive attitude on her own. Alternate law - still flightpath stable but no stops. Direct law - like altn but now you have to trim out the residual stick force after setting the attitude and speed. Nothing there to be confused about.
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Old 17th Jun 2013, 18:29
  #95 (permalink)  
 
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Natstrackalpha

Taking some of your points in turn:

the crew were unaware of the att
You have zero, absolutely zero evidence of this. It is extremely unlikely that the attitude indication was affected and the report offers no evidence to suggest it was.

MUST be a get you out of trouble card.
There is. Its flying power and attitude.

a red button returned everything to direct law immediately
How would this have improved anything. I think the difference between alternate and direct is a red herring. If you are flying too high an attitude it makes no difference if you are in alternate or direct law. Plus. Its as easy to fly an improper attitude in direct as it is in alternate.

a standby altimeter that is working
A standby altimeter would be subject to the same limitations or effects as the main ones. They have a standby altimeter. So what would another one gain you.

Likewise a standby attitude indicator, all appeared to be working, they had a standby and what would another one add?

Last edited by busTRE; 17th Jun 2013 at 18:43.
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Old 17th Jun 2013, 18:36
  #96 (permalink)  
 
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Unhappy BOAC

- why? We believe, do we not, that all altimeters were functioning normally?
Sorry, sorry, sorry I meant to say - stand by Artificial Horizon/ attitude indicator, thus picked up by busTRE

Last edited by Natstrackalpha; 17th Jun 2013 at 18:45.
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Old 17th Jun 2013, 18:51
  #97 (permalink)  
 
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Guyz,

If they had an attitude indicator. why are we here?

If the A/H was operational, then, why did they not look at it? -

See? Their brains curdled into the system . . ?!

If they had looked at it - then they would have recovered the aircraft, instead they were looking at the glistening pinball machine in front of them.

Reminds me of Ka the snake in Jungle book.
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Old 17th Jun 2013, 18:59
  #98 (permalink)  
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Originally Posted by NTA
If the A/H was operational, then, why did they not look at it? -
- welcome back to the fray.
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Old 17th Jun 2013, 19:18
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....and locked on to 6000 fpm V/S then 1400 fpm only after the pilot commanded those RoC's apparently independently of the FD's.
HN39,

You are entirely correct that the pilot would have to be commanding a RoC independently of the FDs for the FDs to default to that RoC when the FDs returned (which the FDs indeed do).

The point you may want to consider is that the FD pitch steering will command an attitude that will provide for the specific RoC in effect at the FD return, in fact the current existing attitude, at least initially.

If the airspeed is continuing to decay, the FD will command a successively higher pitch attitude to meet the Roc requirement that was in effect upon FD recovery.

This commanded continual pitch increase is eventually unsustainable....
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Old 17th Jun 2013, 19:58
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OK, thanks, I understand that.

Figure 69 in the Final Report shows the PF Side Stick Position and the FD Pitch Order.

The graph I reposted in #61 shows the PF Side Stick Position and the Pitch Attitude.

My reply #58 reflects my opinion that the latter shows a closer correlation than the former.
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