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AF447 final crew conversation - Thread No. 1

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AF447 final crew conversation - Thread No. 1

Old 13th Feb 2012, 01:29
  #1321 (permalink)  
 
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As to which turns out "better"
Well, there have been more than one deadly upset events with one system and up to today none with the other.

Tells a story, at least to me.
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Old 13th Feb 2012, 05:21
  #1322 (permalink)  
 
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As to which turns out "better", I guess maybe we'll see as FBW spreads beyond A&B - already in Embraer I think, and filtering down to the bizjets. Have they chosen A-style or B-style ? [I don't know, haven't looked].
Take a look at this article from Flight Global about the Legacy 500 Bizjet: Boeing inspects 787s after aft fuselage composite delamination - FlightBlogger - Aviation News, Commentary and Analysis
(Ignore the statement about Boeing 787-it really is about Embraer.)

Linked sidesticks, C* law but with softer protections in some areas, an AOA limiter, back driven autothrottles, and a different way of doing some things. Looks to be a very pragmatic approach.
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Old 13th Feb 2012, 06:23
  #1323 (permalink)  
 
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Originally Posted by Iceman
Very condescending!

Perhaps you could also grace us with your practical / hands on knowledge and experience of the flying the Airbus. ( An Airbus pilot TRE/IRE, + 20 years military- Rotary(piston/gas turbine) fixed wing (piston and fast jet), 6 years Boeing (757/767) and 16 years Airbus flying A340/A330)
Iceman, I apologize for stepping on the toes of a real Airbus Pilot , however you must admit that in the light of subsequent discussion, your statements were not quite accurate.

I am a retired USN F-4 carrier pilot with ~5000 hrs of civil and military time-virtually all of that involved actual manipulation of the flight controls. I've been the Safety Officer in two squadrons, Maintenance officer in one. I've seen first hand a number of accidents, investigated a number of them, and read thousands of accident and incident reports. I've been studying your Airbus flight control system for the last 2 1/2 years and I think I understand many of the Engineering concepts behind it.

I came to the conclusion 2 years ago that AF447 stalled at altitude and descended in a stall. When I realized how little actual hands-on flying time you folks are getting presently, I knew it must have consequences.

I did not go with the airlines because I realized that in order to make a small fortune in aviation, you had to start with a large fortune.
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Old 13th Feb 2012, 11:21
  #1324 (permalink)  
 
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Machinbird

Apology accepted from one naval aviator to another!

I feel the discussion has got way too "technical" and away from what an ordinary "line pilot" would or needs to understand. I too had 20 years of no A/P nor Flight Director where you had to "fly" the aircraft.
What we have here though is what appears to be a basic airmanship / piloting error, after a relatively minor emergency, as unpalatable as that may be. Blaming the aircraft or airbus for this failing is not good enough. Basic pilot skills of attitude and power would and should have been enough to solve the problem. There also appears to have been a failure in monitoring by the PM and by not taking control and commanding the situation.
The auto-trim did not cause the stall it was trimming the aircraft to assist the pilot, until it cut out. The upset training we carry out always puts emphasis on the fact that the aircraft may be out of trim and manual input may be required to assist in the recovery.
The effort required on the side-stick to achieve the pitch attitude and "zoom" climb was something that should never be applied to any "airliner" at FL350!
My very unscientific "experiment" achieved 13,000/min rod from 'stalling" at 38,000'. But with 15 degrees nose down, some trim, then thrust aircraft recovered by 29,000'.
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Old 13th Feb 2012, 15:20
  #1325 (permalink)  
 
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Originally Posted by Iceman50
I feel the discussion has got way too "technical" and away from what an ordinary "line pilot" would or needs to understand. I too had 20 years of no A/P nor Flight Director where you had to "fly" the aircraft.
Looks like the PPRuNe Administrators have fixed the problem by moving the thread into tech section. It is a natural progression for long term threads it seems.

Iceman, the problem as I see it is that the majority of new guys hitting the airlines do not have the same background and experience that we have acquired, nor will they be getting it in the typical airline flying environment. It is FUBAR, but that seems to be the way things are going. The AF447, and Colgan accidents are representative of this newly developing trend. Where it ends, who knows? In the meantime, the airframe manufacturers had better be looking for ways to protect this new type of pilot better. Whenever I see an area that needs improvement, I try to point it out.

I assume you would be perfectly comfortable, given a sufficiently maneuverable aircraft, to perform aerobatics by instruments at night by with no visible horizon. I get the feeling that the majority of the new airline input would look at you like you were crazy if you asked them to do that.

Different times with new economic factors at work since you and I entered aviation.
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Old 13th Feb 2012, 15:37
  #1326 (permalink)  
 
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Machinbird,

Thanks for the link on the Embraer Legacy 500/450 FBW.
The audio briefing is very interesting.

You mention "Linked sidesticks" but that's not what it is.
Embraer also incorporates a vibrating tactile, aural and visual warnings in the case of an accidental dual input on the sidestick. In this instance, the inputs from pilot and co-pilot are summed together.
Sidesticks are still independants (Airbus way)
Audio describes it between minutes 13 and 21.

As you mention, on the autothrottle side, Embraer did not follow Airbus, and even mentions 2 airbus accidents to justify their choice.

As I understand it also, autotrim under manual flying.
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Old 13th Feb 2012, 18:51
  #1327 (permalink)  
 
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Originally Posted by CONF iture
You mention "Linked sidesticks" but that's not what it is.
Thank you for the correction CONF iture. I see I must have misinterpreted the following statement's meaning:
...."mechanically-linked sidestick controlled all-axis closed-loop fly-by-wire for the aircraft's elevator, rudder, aileron and spoiler; a first for an aircraft of its size."
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Old 13th Feb 2012, 21:24
  #1328 (permalink)  
 
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Originally Posted by Gretchenfrage View Post
Well, there have been more than one deadly upset events with one system and up to today none with the other.

Tells a story, at least to me.
What story does the string of 737 LOCs tell ?

What types are you comparing with what and with what normalisation (flight hours, departures, none(!)) ?

330 vs 777 is about equal on hull losses and hull loss rate, and both have had non-fatal in-flight LOC due to ADIRU failure. 777 has been a lot luckier on fatalities (especially BA38 - engines choked a few seconds earlier and that would have been a lot nastier however good the crew).

340 ? Luckier still on fatalities but more hull losses. Comparable to 777 - not sure appropraite - should twins be compared to quads, should it compare to 747 ?

320/21/18/19 - much different type and usage to 777, compare to 737 against which competes, and hull loss rate is about equal - provided you exclude the older 737s.


The big story is comparing 320 onwards against the old conventional controlled A300/310, and older 737s etc. - the type represents a massive improvement in safety, close to an order of magnitude lower hull loss rates.

If there's a major safety problem with Airbus FBW, it just doesn't show up in the stats - if there is a signal it's hidden by other much larger factors.
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Old 13th Feb 2012, 22:03
  #1329 (permalink)  
 
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inrequentflyer789:
What story does the string of 737 LOCs tell ?
The story of an previously unknown abnormal state of the rudder actuator under specific temperature conditions? Is this comparable?

-Member of The Gretchenfrage Fan Club
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Old 13th Feb 2012, 22:10
  #1330 (permalink)  
 
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Originally Posted by Machinbird View Post
Take a look at this article from Flight Global about the Legacy 500 Bizjet: Boeing inspects 787s after aft fuselage composite delamination - FlightBlogger - Aviation News, Commentary and Analysis
(Ignore the statement about Boeing 787-it really is about Embraer.)

Linked sidesticks, C* law but with softer protections in some areas, an AOA limiter, back driven autothrottles, and a different way of doing some things. Looks to be a very pragmatic approach.
Thanks for that link - very informative. Does indeed look like somewhere between A & B approach, proper moving throttles, but bus-style sidesticks. Ugly chimera or best of both - time will tell. Someone in marketing probably needs firing for naming it "Legacy" mind you...

This has me a bit confused:
Embraer emphasized that the Legacy 500 and 450 are speed stable by design
I think that must refer to failure / direct mode, as the videos look to me to show it controlled like a path-stable airbus (not like 777).
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Old 13th Feb 2012, 22:26
  #1331 (permalink)  
 
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both 330 and 777 have had non-fatal in-flight LOC due to ADIRU failure.
VERY different events IF789 :
  • For the 777 the AP then the pilot followed unrealistic FD commands.
  • For the 330 there was nothing at the time the pilot could have done to prevent the protections to mess up.
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Old 14th Feb 2012, 22:16
  #1332 (permalink)  
 
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upset

Hi everybody,
i agree with most of you, is the lackness of training and too much complacency on the automatism that create a false sense of security among the pilots.
I currently fly one of these A 330 and i see people been slaves of the machine.
Even simple tasks like disengage the ATHR is considered a strange thing.
My background is a solid stick and rudder flying but with time everybody become lazy and don't want to give away the luxory of the automatism.
Yes if you don't touch anything probably the plane still fly by itself but is not easy to not become emotional and nervous in a situation like that
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Old 14th Feb 2012, 22:53
  #1333 (permalink)  
 
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Originally Posted by Organfreak View Post
inrequentflyer789:


The story of an previously unknown abnormal state of the rudder actuator under specific temperature conditions? Is this comparable?

-Member of The Gretchenfrage Fan Club
I was thinking of the 737 LOCs that were actually "lost control", or failure to take control (after automatics fail) of otherwise flyable a/c, not "controls failed".

Say: VP-BKO, TC-JGE, ET-ANB, PK-KKW, OB-1809P, SU-ZCF, VT-EGD

I think I've eliminated cfit and mechanical failure as direct cause from that list.


But the point is not the list, the point is that pilots lose control of 737s as well as A320s, in neither case does it necessarily mean the plane has a bad control system.
Pilots have been losing control of planes for as long as there have been planes, and probably will carry on doing so for as long as there are pilots. And then autopilots will lose control instead (no, I'm not a fan of pilotless either).

Comparing accident rates type to type, competing or old to new, simply does not show fbw as making things worse.

I don't think it shows it making it any better either (newer a/c tend to have better record, fbw or not) - despite all the protections. I don't think that shows anything more than that as a species we're really good at finding new ways to screw up when old ones are closed off...
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Old 16th Feb 2012, 13:16
  #1334 (permalink)  
 
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Before I make my unsolicited comments please keep in mind that the only aircraft I've ever "flown", or piloted, are the type which one uses a radio transmitter with i.e., I know nothing about that which goes on in the cockpit.

After reading this thread since day 1 I've come to the conclusion that many of the comments here, taken together, are a damning indictment of the cockpit crew of this ill-fated flight. After poring over the data, reading the transcripts as provided by BEA, and reading all of the pertinent BEA-provided reports I suppose some of this damning indictment is appropriate.

But I'd like to take this one step further. Isn't the apparent lack of training, as far as the PF is concerned, the lack of CRM, the lack of communication between the flight crew members a further indictment of our modern world? Is not this one specific flight crew a microcosm of our greater world? Is not the underlying reason for the PF's apparent lack of real training yet further proof that "the bottom line" is really the precursor for all that comes after?

I'm involved in the I.T. field and have been for well over 25 years.
I fondly remember "the old days" when the latest innovation in technology was a "big thing". Nowadays I am astounded, shocked and dismayed at that which is coming out of our schools these days. It seems to me the "younger generation" really doesn't have a clue nor do they seem to want one. Apathy, lack of motivation to learn, inattentiveness, self-centeredness etc. These dubious traits seem ingrained in so many these days. Is not what happened with AF447, unfortunately, not another "small" example of all of the above?
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Old 16th Feb 2012, 13:32
  #1335 (permalink)  
 
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rgbrock1

"Nowadays I am astounded, shocked and dismayed at that which is coming out of our schools these days. It seems to me the "younger generation" really doesn't have a clue nor do they seem to want one. Apathy, lack of motivation to learn, inattentiveness, self-centeredness"

Brock, I guess you're referring to American and European kids. Say thay to millions of families in Asia and they won't understand what you're talking about. Have no doubt, there's a transfer of power going on from west to east.
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Old 16th Feb 2012, 15:59
  #1336 (permalink)  
 
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Snoop Naval confidence

Hi Maching Bird,

I liked very much your Naval confidence with Iceman50 (you are the winner).


You said "Whenever I see an area that needs improvement, I try to point it out". That is a noble and generous project.

It seems Iceman50 wants only to avoid a unfavorable AF447 trial in France : This requires that the FRENCH Court has different possibilities :
1. several persons are charged and not only one (for instance AIRBUS, pilots and AF, certification autority, etc. are possible guilty persons) ,
2. The Court is not sure the charged is guilty,
3. The alone charged person did not knew nore understood the danger of his actions, and wanted to kill the passengers and crew from the AF447.

The first way is the easiest with the famous fatal chain, used since years and years by the french lawyers.

Last edited by roulishollandais; 18th Feb 2012 at 16:11.
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Old 16th Feb 2012, 16:20
  #1337 (permalink)  
 
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The Blame Game

I've come to the conclusion that many of the comments here, taken together, are a damning indictment of the cockpit crew of this ill-fated flight.
rgbrock1, I fully realize that you went on to clarify and amend the above comment, but I see a number of "damning conclusions," at least the ones that I myself make, from the comfort of my armchair.

1. Air France, for not changing the substandard pitot tubes fast enough
2. The regulatory agencies responsible for rule-making in reference to the above.
3. Air France training
4. The entire industry, again for the failure to provide proper upset training
5. The pilots themselves, both their, uh, flying skills, and their poor decision to fly into that storm
6. Deficiencies in the Airbus design in terms of lack of tactile feedback in the controls (all of the defifiencies posited by contributors to this thread).
7. Deficiencies in the Airbus instrumentation and control design in terms of stall warning behavior, angle-of-attack display, auto-trim, and the list is long.....

As someone who has NO industry axe to grind, I strongly believe that ALL of the above were dangerous holes in the Swiss cheese, and if any one of the above factors had been not present, the crash might not have happened. I love posting opinions that cannot be proved wrong!
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Old 16th Feb 2012, 21:29
  #1338 (permalink)  
 
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Originally Posted by Organfreak View Post
1. Air France, for not changing the substandard pitot tubes fast enough
2. The regulatory agencies responsible for rule-making in reference to the above.
3. Air France training
4. The entire industry, again for the failure to provide proper upset training
5. The pilots themselves, both their, uh, flying skills, and their poor decision to fly into that storm
6. Deficiencies in the Airbus design in terms of lack of tactile feedback in the controls (all of the defifiencies posited by contributors to this thread).
7. Deficiencies in the Airbus instrumentation and control design in terms of stall warning behavior, angle-of-attack display, auto-trim, and the list is long.....
Some additions maybe:

1.1 AF for (possibly) failing to evaluate adequacy of training and procedure for a known risk (pitot fail) they chose to run as a result of (1). Allegedly when they did in the sim post-447, their crews crashed.

4.1 regulatory authorities (or entire industry) promoting negative (wrong) upset training - one opinion here: The big stall recovery debate - Learmount. To quote:
So the FAA, seemingly without noticing, had authorised a line training technique different than the one they required for type certification.


...and opinions:

6.
Mmm, no fbw should ever be certified then - back to the regulators who approved it. Fbw means only artificial feedback possible, and then can't have proper control feedback in the absence of airspeed info, since proper feedback is dependent on airspeed.

7.
AoA: separate display is designed and implemented by airbus, blame the airlines (inc. AF) who ask for it not to be fitted. And the regulators who have ignored (several) past accident reports recommending it be made mandatory.

SW: same logic might turn out to be common throughout the industry - comments on these threads have alleged that it is there on boeing at least. Just that no one on other types has managed to get measured airspeed below the threshold whilst stalled. Based on info posted here, I think the Airbus BUSS option already "fixes" this issue - unless you get the speed so low the AoA vanes physically stop working. AF of course decided that their crews didn't need no backup speed tape...
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Old 16th Feb 2012, 22:05
  #1339 (permalink)  
 
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Cool

Hi,

1. Air France, for not changing the substandard pitot tubes fast enough
2. The regulatory agencies responsible for rule-making in reference to the above.
Click on for be readable


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Old 16th Feb 2012, 22:44
  #1340 (permalink)  
 
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Organfreak,
In what respect were the pitots 'substandard'?

jcjeant,
AF447 did not encounter the icing conditions (SLD) the NTSB recommendation is addressing.

Last edited by HazelNuts39; 16th Feb 2012 at 23:05.
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