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AF447 final crew conversation - Thread No. 1

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AF447 final crew conversation - Thread No. 1

Old 19th Oct 2011, 08:41
  #221 (permalink)  
 
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Alley oops & TTex600
At long last a sensible reality check on this thread. Well said I too am getting fed up with all these Chuck Yeager brilliant pilots who reckon they would have saved the day.
The Bus is a great aeroplane but it can have it's moments. Bit like her in doors actually.
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Old 19th Oct 2011, 08:41
  #222 (permalink)  
 
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One aspect which I don't think has been mentioned is the basic training these pilots received.

Habits and attitudes are inculcated very early on methinks. What stall training did these pilots have when they were training to be commercial pilots?
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Old 19th Oct 2011, 08:48
  #223 (permalink)  
 
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Originally Posted by rrr
on the AB in ALT2 Law he could simply let go of the stick.
Did he do that?
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Old 19th Oct 2011, 09:06
  #224 (permalink)  
 
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1) Would a 'Boeing' trim the tailplane fully nose-up all on its own in the same situation? (NB talking manual input now, not A/P)

2) Would a 'Boeing' cease a stall warning in the same situation?

3) Is the 'transition' between one set of control laws in a 'Boeing' with degraded IAS inputs as complicated as with the 330?

4) Would the instrument displays in a 'Boeing' degrade the same way?

5) Would the 'Boeing' physical 'stick shaker' acting over the same period have more or less impact on PF than a voice warning?

6) Would the 'Boeing' stick displacement give a clearer indication of control input to another pilot?
I'm no Boeing pilot so I can speculate as Boeing pilots do about Airbus:

1) Boeing don't seem to be very famous in communicating very well with crews if it comes to aural warning. Helios Athens springs into my mind...

2) If you are overloaded with aural warnings, it is rather unimportant if the aircraft suppresses one or the other warnings. I speculate that a Boeings flight crew wouldn't hear it neighter. Birgen Air shows in front of my eyes.

3) you are right that there are no different "laws" on a B. But you don't have to know in which law you are in in an Airbus to handle the aircraft correctly. That's why you never find a word of "law" in your Airbus checklists. It's - from a practical stand point - irrelevant. Just fly the aircraft as if it would be a normal aircraft, and you will do the correct thing - in any law.

4) almost certainly. It's called unreliable instruments and its main feature is that instruments degrade. Boeing don't seem to have a very much lower loss-off-control record lately... (Beirut accident, others)

5) a wrong sensed stick shaker would increase the turmoil in the cockpit considerably. And it's most certain that the stick shacker would have come on.

6) no it wouldn't, because the guy pulled the stick on purpose, his hand was not "forgotten there". He pulled for the only reason that he wanted to pull. Because people told him that you can do that on an Airbus any time.

All in all, no, you are not correct at all by assuming that a Boeing would have been safer in this situation. The only difference was that these pilots knew that they are in an Airbus and thus thought they could misshandle the aircraft.
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Old 19th Oct 2011, 09:17
  #225 (permalink)  
 
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Hi HN39
Did he do that?
No he didn't.
He injected a couple of small nose down inputs on the way to the stall, then once he was stalled he continued to assist the aircraft, which was attempting to hold the requested 15 nose up, with the use of full back stick.

Hi Dani,
Just fly the aircraft as if it would be a normal aircraft, and you will do the correct thing - in any law.
I wish that were true. Have a look at QRH 1.26 Windshear. It mentions the use of Full Back Stick twice on that page. A conventional aircraft would mention "respect the stick shaker". There is a different mind set to flying the AB.

Hi fireflybob,
What stall training did these pilots have when they were training to be commercial pilots?
I don't know what AF pilots had, but the only aircraft I've stalled is a Piper Cherokee when I was training and a TriStar during an air test. I've been to the stick shaker in the simulator in previous aircraft types and then recovered.

In the simulator I've had the demonstration that's it's impossible to stall an AB in Normal Law no matter what stupid inputs I was invited to make (like full back stick) at very low speeds.
Our new simulator package now includes Alt Law at FL 350, reduce speed to the "Stall" warning and recovery.

Last edited by rudderrudderrat; 19th Oct 2011 at 10:41. Reason: Dani reply
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Old 19th Oct 2011, 09:24
  #226 (permalink)  
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Originally Posted by dani
All in all, no, you are not correct at all by assuming that a Boeing would have been safer in this situation.
- ??? Who said that? Not me. Read the post again.
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Old 19th Oct 2011, 10:10
  #227 (permalink)  
 
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Originally Posted by dani
3) you are right that there are no different "laws" on a B. But you don't have to know in which law you are in in an Airbus to handle the aircraft correctly. That's why you never find a word of "law" in your Airbus checklists. It's - from a practical stand point - irrelevant. Just fly the aircraft as if it would be a normal aircraft, and you will do the correct thing - in any law.
You can't "fly the aircraft as if it would be a normal aircraft". It isn't a normal aircraft and doesn't fly like one. It auto trims and gives no tactile feedback. A true aviator flying a normal aircraft uses touch and sight. The Airbus takes touch out of the equation, which effectively forces the pilots eyes to be the only sensor.

To bring this back to the topic, CVR shows that the AF447 crew, three trained and experienced pilots, was confused by what they saw and acted improperly. We, the aviation community, need to understand why they failed to recognize their condition. Continually claiming that the aircraft is just another aircraft diverts attention away from the effort to understand why they were confused to the point of death.
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Old 19th Oct 2011, 10:25
  #228 (permalink)  
 
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@Dani

The examples you mention are with conventional Boeings, no FBW T7 incident.

Therefore irrelevant. I am sure all Airbus freaks would turn in disgust and discard any reference to non-FBW 300 or 310 incidents.

Apples with apples please
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Old 19th Oct 2011, 10:44
  #229 (permalink)  
 
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A true aviator flying a normal aircraft uses touch and sight.
Oh, I didn't know. So in your opinion all fighter pilots nowadays are no true aviators anymore... - gives me comfort when I share my cockpit with them (I can promise you, they still are). I never understood the "tactile feedback concept" on modern airliners since you are not getting feedback at all but working against springs and hydraulic units. Let alone these clumsy scratching autothrottles that are never completly aligned and where you spend most of your brain capacity to figure out how to put them in the position you want them (and they move again away from there).

No let me tell you, a true aviator is the one that understands that every aircraft is a true aircraft, that you have to handle her gently, moderatly, sensibly, intelligently and foresightedly. You can bring down every aircraft if you want to, be it an A300 American Airlines over NY 2001 with weired rudder input, or forgetting moving throttles like Turkish in Amsterdam. It's not easy, but you can do it. If you are no true aviator. They are spread over A and B about evenly...

Last edited by Dani; 19th Oct 2011 at 11:40.
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Old 19th Oct 2011, 12:27
  #230 (permalink)  
 
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Habits and attitudes are inculcated very early on methinks. What stall training did these pilots have when they were training to be commercial pilots?
Are you trying to imply that somehow they were awarded a CPL without stall training? It is really ridiculous that some on here are trying to imply that they couldn't recognise a simple stall. Clearly there were was a lot of confusing feedback in the cockpit.

FWIW, the French CPL syllabus contains a great deal of stall training - full stalls, incipient stalls, stalls in the turn, stalls in different configurations, stalls without airspeed reference, stalls at constant deceleration, all under the hood. But as others have pointed out, recognising and dealing with stalls in a light aircraft is a very simple matter compared to in a complex heavy aircraft at altitude.
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Old 19th Oct 2011, 12:31
  #231 (permalink)  
 
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Can I state the obvious here and ask how do we know this was from the CVR?

You have the French government investigating a French airline crashing a French Aeroplane. The French have much to lose if it is proven there is some design flaw in the A330. Saying that they're not releasing the CVR then releasing some part that makes the pilot's look like fools raises my suspicions. There were also some convenient leaks to Bloomberg that pointed the finger at the pilots earlier in the investigation.

So how about we get to listen to the ACTUAL CVR with all the bells whistles and God knows what else before we pass judgement.

It is quite possible that the pilots made a mess of the whole situation but without hearing the entire CVR I for one am not buying the current story. To many things have fallen into place for Air France and Airbus for my liking without releasing the CVR for public consumption.
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Old 19th Oct 2011, 13:00
  #232 (permalink)  
 
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This is not about the CVR neville_nobody.
This is about the FDR first :
Why the Judge refuses to include the full FDR data to the procedure ... ?
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Old 19th Oct 2011, 13:06
  #233 (permalink)  
 
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I have a very basic general aviation question. In my limited unusual attitude training the "golden rule" was to unload the airframe and "step on the sky" and then adjust pitch and power as needed. I am still at a complete lose to understand the PF's initial actions here.

I am also somewhat confused about how the AB functions. My understanding is (please correct if wrong) is that the AB retains the last input if you release the stick...it would seem that this robs the pilot of a very important tool in unusual attitude recovery. I realize that technically the 330 was not in an unusual attitude at AP disconnect...however in the conditions the PF did not really know his attitude at that moment.

I find myself constantly amazed at the proportion of professional pilots who seem to feel the need to defend such a basic lapse in airmanship. This is not
a failed attempt to resolve a mechanically induced event. From every indication the PF flew the airplane into a stall (no "autozoom").

Once in the stall I cannot fathom that at no time was the airframe unloaded or did the pilot give any indication he was actually responding with any meaningful intent to explore his flight envelope.
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Old 19th Oct 2011, 13:21
  #234 (permalink)  
 
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Are you trying to imply that somehow they were awarded a CPL without stall training? It is really ridiculous that some on here are trying to imply that they couldn't recognise a simple stall. Clearly there were was a lot of confusing feedback in the cockpit.

FWIW, the French CPL syllabus contains a great deal of stall training - full stalls, incipient stalls, stalls in the turn, stalls in different configurations, stalls without airspeed reference, stalls at constant deceleration, all under the hood. But as others have pointed out, recognising and dealing with stalls in a light aircraft is a very simple matter compared to in a complex heavy aircraft at altitude.
Trim Stab, not at all and thanks for the information.

But I would be interested to trace all relevant training that these pilots have had back to initial. If they seem unable to recover from a stall (and yes I agree there many other factors here) then this is a product of the overall "system" part of which is their training at all stages.
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Old 19th Oct 2011, 14:01
  #235 (permalink)  
 
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Hi DozyWannabe,
Had he let go of the stick, the "soft" AoA protections available in Alternate 2 would have corrected the pitch back to a safe level.
I don't have a copy of FCOM for A330 so my source is very dubious:
http://www.smartcockpit.com/data/pdf...light_Laws.pdf
Please see note 17) "Protection totally lost if DUAL ADR failure or ADR disagree."
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Old 19th Oct 2011, 14:14
  #236 (permalink)  
 
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You're right, I was forgetting that it was Alt 2 (No Prot), the soft protections would not have been active. I'll flag that in my post.

That said, even with the trim the way it was, the extreme attitude was being held with the elevators - letting go should have brought the nose down to some degree - so in that regard the only difference between conventional and Airbus controls is that more physical effort needs to be expended in the case of the former - I'm told that it does take a fair amount of effort to hold the Airbus SS back against the stop for any length of time - considerably more force than it would take to hold a home computer analogue stick in the same position.

I go back to what I was saying the other day though, sometimes the best thing is to do nothing at first and allow the aircraft's inherent stability to ride the problem out - if the problem doesn't improve, *then* it's time to make positive corrections, albeit gently at first unless you're *very* sure of what you're doing.
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Old 19th Oct 2011, 14:43
  #237 (permalink)  
 
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Originally Posted by Gretchenfrage View Post
As a simple user, however, I only judge by crashes and my PC does that regularly more often than my two Macs.
How much did you pay for your PC versus your two Macs? You'll find a lot of the time it's due to volume manufacturers using cheap components, whereas Apple (as well as premium Wintel manufacturers) tend to cherry-pick theirs. Windows' file system requires more user maintenance over time than a Un*x-based equivalent. The machine I'm typing this on has crashed precisely once since I installed it, and that's because I was doing low-level development - it's running Vista, which is commonly regarded as the worst NT-based OS Microsoft have released. This is because I built the thing myself from top-grade components and I know how to maintain it, however I recognise that's a route that may not appeal to everyone.

Now wasn't it Airbus who pretended to make a system that's easier in it's operation? Wasn't that the main selling argument? Less pilot training due to easier operating and better protection?
It is easier in normal operation, there's no question about that. Like all complex machinery though, the issues occur when things go wrong.

I'm not convinced that the "less pilot training due to easier operating and better protection" wasn't a misunderstanding of the press, or possibly Airbus's marketing department. Airbus's sales pitch has always been about less *conversion* training between its FBW models compared to other manufacturers. The safety aspects of the protections and FBW systems were a separate issue, and were backed up by some *very* distinguished pilots during the development phase.

It seems they got caught out by their own pretension. Almost all Airbus defenders today however shift to the argument that lack of system-knowledge caught the AF pilots. - A distinct change of paradigm!
The same as it would have been in any other aircraft. You can't get away from the fact that immediately pulling the stick back upon FMC disconnection was the precise opposite of what should have been done on a basic airmanship level, let alone anything above that.

In fact from my reading it has been the anti-Airbus crowd that have been arguing that the systems are too complex and that the pilots could not possibly have understood them. Those who I know are actual Airbus crew have always maintained that the system is designed to be flown like any other aircraft and that the only thing one needs to remember is the loss of hard protections once outside of Normal Law.

Even if the underlying programming of a T7 is more complex, its operation is simpler and more easy to grasp and operate for pilots.

I largely prefer that and it seems to work better.
That is your opinion and you are very much entitled to it, but that does not make "T7 = better" incontrovertible fact. The very fact that people are talking about "real" aviators flying by feel suggests that at the heart of this distrust lies some bitterness at the romantic aspect of flying going the way of the dodo, but Airbus are not solely responsible for that - it's just the way things go.

With the knowledge I have now, had I been born a decade earlier I could have been happily ensconced on a six-figure salary with automatic respect from management for the technical decisions I make. Things changed and my skills are much more commonplace now, but I don't waste my time being bitter and grouching about it.

Up to now there is no victim to be mourned from a T7 accident.
That counts a zillion, at least to me.
That could have been very different but for the skill of the crew at the controls of BA038 - don't forget that!
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Old 19th Oct 2011, 15:03
  #238 (permalink)  
 
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Agreed, because they could oversteer the protection ......
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Old 19th Oct 2011, 15:43
  #239 (permalink)  
 
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IF

If the last ten minutes had been a sim session....

Pass? Fail? Suspension? I try not to put my feet into this pilot's moccasins, at least not very often.

Dozy: At A/P disconnect, He did not pull "Full back stick".

Master Caution. Cavalry Charge. Loss of Auto Throttle.

First knock. Identify and correct. Manual control required. This means the ship will need handling if the flight path wanders, no a/p to arrest a bad. He input roll left and nose up. I assume to correct a deviation in S/L flight.

Does he know Speeds are duff? Immediately? Because without knowing that, there is immediate danger. Any handling will tip a baseline attitude, and Pitch and Power becomes more difficult. Like an instructor who cobbles together an UA whilst you look at the floor. When you take over, you need a quick and correct read, a nails scan that drives everything you will do subsequently, to recover the aircraft. Did you blow it? Switch off, let's start over.

A nightmarish sim session such as the real deal 447 encountered would have failed (pick a percentage) pilots. Prolly everyone here.

There is no record established to condemn without conclusion. This was one off. Every accident is.

Sim? "Follow me through, right, this, not that. Pass. Off you go." Except for one thing. Not even the Sim could be recovered. The flaws were known, the workarounds were "best guess", not best practice, and the equipment was ready to fail.

He was not ready. Nor was PNF, and later, the Captain. The salient issues remain, and absent the full record, I couldn't possibly condemn this crew. Nor should anyone. Should the full record establish PE as the main cause, it will still be difficult to condemn. The environment that presented at 447's fatal entry was pre-ordained by Human error, and a confluence of Natural and Unnatural settings.


rudderrat. "He was assisting the a/c in maintaining 15 degrees nose up."(At STALL).

This is what I meant earlier when I suggested he may have been attempting to trim into the climb, rather than commanding it. With TOGA, and an effort to PITCH at 15, he is responding to windshear? Now that is not cute, but, in an effort to understand what presents as a rather inexplicable record of manual control, what was in his head? Did speeds indicate a shear? Was there a WARN? There is a record of ACARS that shows a Mx message re: shear and TCAS. If slow (did he know?) how is windshear at altitude different than at lower levels? (To him?) There is still a danger of STALL, and how was he to know the STALL (WARN) wasn't the result of actual shear? How does he know without the normal cues that he is STALLed and needs to recover the STALL? If he is confident the STALL WARN is approach to STALL, when is he supposed to "get" that the a/c is actually STALLed?

Near top of climb, and for whatever reason, this aircraft was essentially operating at what presented as low altitude. Low speed, PITCH up, and clean. Plus quiet, at least until the RoD increased. That is a domain that triggers certain things in all pilots, and I venture it would be difficult to not lapse into muscle memory with all those familiar (but wrong altitude) cues?

Reason enough to not Push the Nose Down? A mistake, of course, but since there never were STALL responses, a mistake quickly forgotten, and an interruption in continuity, repeating all the way down.

There was no recognition of STALL, by anyone. Now one can condemn utterly this crew as incompetent, and an absolute aberration in performance. That would be ill advised. It assumes there were no reasons to behave as they did, which is triply absurd.

Last edited by Lyman; 19th Oct 2011 at 16:01.
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Old 19th Oct 2011, 16:29
  #240 (permalink)  
 
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Slightly O/T, I admit. Just to close this O/T subject.

Originally Posted by Octane View Post
Cyflyer,
I believe ChritiaanJ is an ex Concorde pilot, he would know.........
I wish...

No, I was a flight test support engineer for the Concorde AFCS in the earliest days, and I got drawn back into the 'Concorde world' after the 2000 crash... like many, I asked myself "what did we do wrong, for this to happen?"

The Concorde 'barrel rolls' may sound like an 'urban legend', but they've been confirmed by enough truly reliable witnesses....

And no, I didn't get the impression that Jean Franchi had "formal" permission from the Flight Test Director at Toulouse (Turcat) for each of his barrel rolls.....
It could be done... and he did it.

PS, strictly for the MS FlightSim pilots on here.... (no, I'm not one, although I tried to help out with some of the system issues for the Concorde 'add-ons'): you can 'barrel roll' Concorde quite realistically.
But AFAIK, nobody has ever 'looped' a Concorde (as in the movie), even in FS, and even less in the real world.

Last edited by ChristiaanJ; 19th Oct 2011 at 16:45.
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