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AF447 wreckage found

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AF447 wreckage found

Old 8th Jun 2011, 17:41
  #1501 (permalink)  
 
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RWA, I went back a few pages to try and figure out the context of that which you isolated, and could not find the post. I think what was in my mind was that we have had a number of different mishaps and incidents discussed here, and pitot anomalies have been featured in either family of aircraft. (As contributing causes to incidents or mishaps/crashes).

I am not sure if I sensed an AB bash and was responding to that, or why I phrased it just so.

So I can't answer your question, as I am not sure what post (in total) you were referring to.
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Old 8th Jun 2011, 17:46
  #1502 (permalink)  
 
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@ Goldfish85

There you are:

http://www.aaib.gov.uk/cms_resources...%2006-2001.pdf
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Old 8th Jun 2011, 19:56
  #1503 (permalink)  
 
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1491-Excellent analysis regardless of accident findings

As much as the author of 1491 has spent in the Airbus , I have spent in Boeing and Douglas aircraft and although I finished my career( 26,000 hrs) in glass cockpits I consider myself a "steam gauge" pilot. In the days when we have the glass all over the place the problem in recreating this scenario will be determining "what the pilots saw"....what information was given to them and what screens were just blank?
Not too long after the Delta L-1011 crashed at DFW the airlines came up with an AAMP (Advanced Aircraft Maneuvering Program) that was meant to show the pilots of transports how to get max performance out of their aircraft...one thing we at our airline found out that when the sim was put out of the normal flight envelope and then handed over to blindfolded flight crew they were able to recover the aircraft by reference to the attitude indicators and airspeed alone....EXCEPT for our Airbus sims...all the screens went black with a big RED X across them...apparently since they were outside their flight envelope ...I say apparently because we could never get a response from Airbus on why this occurred except the same caveat I read in response to the professor from University of Berlin ...face it , if any fault is laid at the Airbus door for bad design/ cause of accident, that will be the end of Airbus....and the EU will not stand by for that....blame the pilots , they can't talk back.
There's been enough doubt cast over the whole Airbus laws of control to warrant a serious review....One thing I do know....if I wanted to split -s a 747 from FL 410 , it would roll over and do what I asked it to . Nobody here has shown that the Airbus would or could. I am not trying to say that they don't have some great features but for 3 and one half minutes three very qualified pilots tried to avoid dying and were unable to do so because either they didn't know what was REALLY happening or because they couldn't do anything about it. Either way AIRBUS owes them and us a better answer than WE need more training...maybe they do in how to design Pilot's airplanes...
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Old 8th Jun 2011, 21:02
  #1504 (permalink)  
 
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Was this significant in terms of priorities and delays,

the commander took manual control of the aircraft because neither autopilot would engage.
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Old 8th Jun 2011, 21:50
  #1505 (permalink)  
 
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As much as the author of 1491 has spent in the Airbus , I have spent in Boeing and Douglas aircraft and although I finished my career( 26,000 hrs)...
Daddy,

I have zero hours in a simulator, but I am pretty positive that simulators can only accurately reproduce the real life data they have been fed.

Meaning that unless Airbus or Boeing deliberately fly an aircraft outside its envelope, and record the data, the simulator will not be able to reproduce accurately the aircraft reactions.
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Old 8th Jun 2011, 21:51
  #1506 (permalink)  
 
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Guys,

The mid-atlantic A340 zoom climb has little bearing on the AF447 accident. Try reading the reports.

The high speed protection was triggered by turbulence and the aircraft did what it was designed to do.

The AF climb was pilot induced, it's there in the report quite explicitly. Why the pilot made nose up inputs is the real mystery here and it may possibly have something to do with his airspeed reading.

The high speed protection was disabled when the aircraft went into alternate 2 law and was never available.
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Old 8th Jun 2011, 22:08
  #1507 (permalink)  
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"...The AF climb was pilot induced, it's there in the report quite explicitly..."

No it in't. BEA made NO conclusions, they only reported data. YOU say it was PF induced, conclusively. There is a mild difference.
 
Old 8th Jun 2011, 23:22
  #1508 (permalink)  
 
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Good post 1491 (Basil) interesting in that the upper air handling is a challenge. BEA say trim was 29% usually that would be 38% I.e more aft.. That may be because of the AF configuration.. (note the cofg moves aft in flight due fuel transfer to tail) which makes the a/c even more sensitive in pitch.
I agree IMHO a very very difficult situation when one takes surprise/shock into account.
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Old 8th Jun 2011, 23:35
  #1509 (permalink)  
 
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Sim programming

WilyB,

The sims have a sets of equations describing everything from Engine Performance to turbulent weather to day/night to ACARS ...the data points to create that would take decades if they were collected and then programmed. The whole idea of the sim is it will do exactly what the plane would in the real world....if they had to program captured data points that means that the below glide slope approach some guy flew in the sim wouldn't be possible unless they'd captured the data points beforehand....the whole reason they can train pilots to fly the 787 or 380 before the plane ever flies is because they have detailed equations to describe all phases of flight....what happened to our Airbus sims is that the equations only described what the programmers in Toulouse expected pilots to see in normal flight regimes.

Last edited by captdaddy; 8th Jun 2011 at 23:37. Reason: additional info
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Old 9th Jun 2011, 00:51
  #1510 (permalink)  
 
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Man Flex,
I agree with you.

From the AF447 report: From 2h 10min 05sec, the autopilot then auto-thrust disengaged and the PF said, "I have the controls". The airplane began to roll to the right and the PF made a left nose up input. The stall warning sounded twice in a row. At 2h 10min 16sec, the PNF said, "So, we've lost the speeds" then "alternate law". The airplane's pitch attitude increased progressively beyond 10 degrees and the plane started to climb."

It certainly sounds "quite explicitly" to me. It is reported data, no conclusion necessary.

Relative to the mid-Atlantic A-340 zoom incident, I agree that was different in many respects. To begin with, erroneous speed was not the reason for the AP/AT disconnect, as was the AF447 AP/AT disconnect. For AF447, one of the first fault messages with cockpit effect was "PROBE-PITOT 1X2 /2X3 / 1X3 (9DA)", and IMO, this is what caused the AP/AT disconnect and lead to the cascade of subsequent events.
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Old 9th Jun 2011, 01:27
  #1511 (permalink)  
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"From the AF447 report: From 2h 10min 05sec, the autopilot then auto-thrust disengaged and the PF said, "I have the controls". The airplane began to roll to the right and the PF made a left nose up input. The stall warning sounded twice in a row. At 2h 10min 16sec, the PNF said, "So, we've lost the speeds" then "alternate law". The airplane's pitch attitude increased progressively beyond 10 degrees and the plane started to climb." "

Show me where, exactly, this concludes (or even says) that the Climb was initiated by the pilot. Careful.
 
Old 9th Jun 2011, 01:59
  #1512 (permalink)  
 
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The whole idea of the sim is it will do exactly what the plane would in the real world....
Daddy,

I am sure you are correct, and with my 0 vs. your 26K hours of flight SIM who am I to argue, but the Airbus and Boeing actual test pilots appear to have a very different point of view.

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 pilors 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 aerodynamic 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. If should be obvious that 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 nol far from the centre of the flight envelope; the pari 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.
http://www.ntsb.gov/Events/2001/AA58...its/240005.pdf
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Old 9th Jun 2011, 02:13
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I've had an opportunity to discuss this with a friend of mine who flys military A330s. He hasn't had a chance to read the report, but when I queried him on the pilot's maintenance of a nose-up attitude, his only explanation was that they believed they were in an over-speed situation, rather than a stall.

Incidently, I flew from London to Sydney on A340s several days ago, and I couldn't help but imagine the aircraft falling from our cruise in little over 3 minutes! It was the first time I've EVER felt uncomfortable on an aircraft. This should never have happened, and the boffins who design these modern marvels need to make sure the pilots retain the authority and ability to recover an aircraft in distress.

Someone else mentioned that a 747 would 'roll over and do what you want it to' in such a situation. I can't comment on the differences between the two manufacturers, but it would appear to me from various comments I've read that Airbus needs to incorporate some slightly more pilot-intuitive aspects to the way the aircraft relates to its crew.

As a pilot who trained in the military, I'm still shocked and dismayed by the chain of events that unfolded.
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Old 9th Jun 2011, 02:30
  #1514 (permalink)  
 
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Poit, the Airbus people will say you are trying to send technology back 25 years so you must adjust to total automation. Pilots now manage autopilots and the computer because it can do it better most of the time. Handflying skills are no longer required.
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Old 9th Jun 2011, 02:33
  #1515 (permalink)  
 
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Poit

It was the first time I've EVER felt uncomfortable on an aircraft. This should never have happened,
I agree: what's wrong with you?
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Old 9th Jun 2011, 03:20
  #1516 (permalink)  
 
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Bubbers44: Clearly hand-flying skills ARE still required, as this accident tragically illustrates. Hence my point. Sure, computers can do a better job, but when they decide to pack it in (as happened in this case) the pilots need to have a pilot friendly and intuitive aircraft to fly. A combination, therefore, between the highly advanced, and old-school simplicity.

WilyB: LOL. This accident (and several others...such as the QANTAS A380) has made me question that pilots are system operators, and no longer aviators. Thankfully the QANTAS event ended without any casualties, but it could have quite easily gone in another and far more horrific direction.

These things never happened in the old, classic 747's. Maybe it wasn't so bad 25 years ago Bubbers!
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Old 9th Jun 2011, 03:35
  #1517 (permalink)  
 
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Bubbers44

We know you despise Airbus and do not understand it, so please no more useless posts.


Captdaddy

Do not know what kind of simulator you were flying but when I taught unusual attitudes the instruments never went to big red crosses. Ever heard of controlled precession, because you can see it in the simulators I have "flown".

BASIL's CUT and PASTE

The post that was copied and pasted from the "one of the most experienced A330 pilots in the world". A lot of what he has said is absolute rubbish and you would not think it came from such an "experienced A330 pliot", e.g. you would not want to follow the FD's if you were in AF447 position as it would be giving erroneous information. Altitude is the least of your concerns at that point in time, ATTITUDE and POWER are the life savers. If you have stalled, you MUST unstall the wing and add power progressively to be able to counteract any pitch up due to the low slung engines. As for the thrust going to climb power it freezes at the setting just prior to disconnect, with the Thrust Lock function. The non-moving thrust levers are NOT an issue. If you disconnect the A/THR you match the blue 'donuts" then disconnect, in the AF case the thrust levers could have been left in the detent and moved to the correct power setting when required. Even if it went to climb thrust there would not be a huge increase in thrust and you certainly would not stall. As for never being trained in stalling, you never train to stall in the simulator, but most regulators require approach to the stall recovery training as part of the Type rating requirements. But there again what would I know only been flying the Airbus A330/A340 since 1996 and for those that wonder flew 757/767 for 6 years before that, so seen both manufactures!
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Old 9th Jun 2011, 05:00
  #1518 (permalink)  
 
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Iceman, given your experience with both major manufacturers, do you have a theory as to what went wrong on this occasion? I'm not being sarcastic in asking that, just want the benefit of someone who's got experience with these aircraft.

Is there a difference between Airbus and Boeing (you might not want to answer that)?
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Old 9th Jun 2011, 05:27
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I asked a question earlier but it was one of several and did not get answered with the others.

The glass indicates when the ASI is unreliable and the autopilot disengages as its inputs don't agree.

Is there anything that sounds etc to say that the ASI has become reliable again? Would it be possible for pilots, perceiving the ASIs to be intitially wrong to continue to do so to the exclusion of paying attention to attitude?

Just how tight is coffin corner at FL 380?
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Old 9th Jun 2011, 05:29
  #1520 (permalink)  
 
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These things never happened in the old, classic 747's
No, they never did:
Air India 747

KAL 747

Air China 747

As for the thrust going to climb power it freezes at the setting just prior to disconnect, with the Thrust Lock function
There are failure modes, including inadvertant disconneciton, where they do run to full (CLB) power.

...and the boffins who design these modern marvels need to make sure the pilots retain the authority and ability to recover an aircraft in distress.
How can you conclude the "boffins" have not made sure of this in the AF A330 crash? In the TC incident, they had the ability (but "chose" not to use it) to control the aircraft. As the above links show, the "boffins" add these protections in an attempt to increase safety. Some of the above accidents could not occur in the same manner in a FBW Airbus...

I am not overly for or against the Airbus v Boeing philosphy - I have flown both. But until we get a full analysis from the BEA, it is hard to see whether the FBW "laws" were a (significant) factor.
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