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AF 447 Search to resume (part2)

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AF 447 Search to resume (part2)

Old 25th May 2011, 00:59
  #2321 (permalink)  
 
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mm43

Do you know if they have continued recovering debris/bodies at the crash site? I am just curious to know, or whether they have given up.

tks.
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Old 25th May 2011, 01:01
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OK465 (post 2292) -

"BOAC, you are correct, "most" is a relative term. The NG's I've dealt with have had AOA since 2001. I'm only familiar with specific carriers and all (not most) of their NG's have it."


I've been told by someone involved with the AOA program years ago that only AA and DL have ordered that option in the U.S. What carriers have you seen have the AOA gauge on the PFD and/or HUD?
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Old 25th May 2011, 01:29
  #2323 (permalink)  
 
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promani
Do you know if they have continued recovering debris/bodies at the crash site? I am just curious to know, or whether they have given up.
I have no information, other than the "Ile de Sein" has returned to the ROP following a crew change in Dakar.

My understanding is that the BEA may still be searching for the missing SSFDR ULB, and there could be other items they wish to recover. The BEA has made it clear that the recovery of bodies is not their mission, and IIRC the French courts have stopped any further recovery of bodies. DNA has been successfully extracted from those brought to the surface, and what may happen next is unclear.

The BEA may have something to say on this matter at their next press release.
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Old 25th May 2011, 02:30
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Cool

Hi,

and IIRC the French courts have stopped any further recovery of bodies.



Wednesday, May 25, 2011

Two years after the disaster that has killed 228 on 1 June 2009 off the coast of Brazil, two judges wrote to warn families that the remains would not be too damaged up from the bottom of the Atlantic.

« Pour préserver la dignité et le respect » des victimes et de leurs proches, « nous avons pris la décision de ne pas relever les restes trop altérés », écrivent les magistrats Sylvie Zimmermann et Yann Daurelle, dans un courrier dont l'AFP a eu copie. "To preserve the dignity and respect" for victims and their relatives, "we made ​​the decision not to raise too remains altered," wrote the judges Sylvie and Yann Zimmermann Daurelle in a letter which AFP has been copy. Par conséquent, « il a été décidé de ne remonter que deux dépouilles dans des états différents de conservation, afin de déterminer si l'identification est ou non réalisable après un long séjour au fond de l'océan ». Therefore, "it was decided not to recover only two bodies in different states of preservation, to determine if the identification is not feasible or after a long stay at the bottom of the ocean."

En fin de semaine dernière, deux corps de passagers ou membres d'équipage de l'A330 du vol AF447 ont été récupérés. By last weekend, two bodies of passengers or crew of the A330 flight AF447 were recovered.
Victims in a degraded state

« V ous devez savoir que les dépouilles des victimes se trouvant par le fond sont inéluctablement dans un état dégradé à la suite du choc particulièrement violent, du temps écoulé et du milieu environnant », préviennent les juges.
"Y ou should know that the bodies of victims lying in the background are inevitable in a degraded state of shock after particularly violent, time elapsed and the surrounding environment," warn the judges.
de plus, « la remontée à la surface est nécessairement un facteur supplémentaire de dégradation ».
again, "the ascent to the surface is necessarily an additional factor of degradation."
« Par conséquent, nous ne procéderons qu'au relevage des victimes que l'on peut décemment remettre aux familles à condition qu'elles puissent être identifiées », écrivent-ils.
"Therefore, we will only lift the victims that can deliver decent families provided they can be identified," they write.
« Dans l'hyptohèse où l'identification se révélerait impossible, nous estimons que le respect des disparus et de vous-mêmes commande qu'ils reposent en paix dans leur dernière demeure », concluent les juges.
"In hyptohèse where identification would be impossible, we believe that respect for Missing and control of yourself they rest in peace in their last home," concluded the judges.
Quatre spécialistes de l'Institut de recherche criminelle de la gendarmerie nationale (IRCGN) vont rejoindre les équipes déjà sur place, précisent les magistrats, jugeant « impossible de prendre une décision qui rencontrerait l'agrément de l'ensemble des familles françaises et étrangères ».
Four specialists from the Institute of Criminal Research of the National Gendarmerie (IRCGN) will join the teams already on site, say the judges, saying "Unable to make a decision that is acceptable to all French and foreign families" .
La semaine dernière, Jean-Baptiste Audousset, président de l'association Entraide et Solidarité AF447, avait jugé que le repêchage du premier corps ouvrait une phase « très difficile » voire « traumatisante » pour les familles qui y sont opposées.
Last week, Jean-Baptiste Audousset, president of the Mutual Aid and Solidarity AF447, determined that retrieval of the first body opening phase "very difficult" or "traumatic" for families who oppose it.
De leur côté, les familles brésiliennes veulent que tous les corps soient remontés.
For their part, the Brazilian families want all the bodies are assembled.
Google Vertaling

Original:
Rio-Paris*: pas de remontée des corps trop abîmés - lesoir.be

Unfortunately, a number of people already died in a field near Schipol to disprove that.
Having throttles move via actuator to show current thrust level and trending, like Boeing does, would be a start.
I wonder how many (they are unknow of course ) people already survived to prove that ........

Last edited by jcjeant; 25th May 2011 at 02:45.
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Old 25th May 2011, 02:58
  #2325 (permalink)  
 
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Reliability: a measure of the success with which a system conforms to some authoritative specification of its behaviour.

Safety: Freedom from those conditions that can cause death, injury, occupational illness, damage to (or loss of) equipment (or property), or environmental harm. Given that interpretation, it is then fair to say that there is no safe airplane.

When the behaviour of a system deviates from that which is specified for it, this is called a failure. Failures result from unexpected problems internal to the system that eventually manifest themselves in the system's external behaviour. These problems are called errors and their mechanical or algorithmic cause are termed faults. Systems are composed of components which are themselves systems: hence;
> failure -> fault -> error -> failure -> fault

Software doesn’t deteriorate with age: it is either correct or incorrect but faults can remain dormant for long periods. Ada is very much alive and well. I find it considerably amusing to read posts where the author assumes Ada to be a stale dinosaur - they seem to be quite far removed from reality. We use Ada for commercial projects achieving superior results in comparison with other languages - fewer bugs reach binary, easier to maintain code, certified and tested compilers, self documenting, and standards that read with legal precision... to name a few benefits.

I don't have a problem with the software engineering practices used in avionics. But I am weary of impacts on safety caused by time-cost demands.

There is a list of mechanisms that could make aircraft 'safer' but they aren't implimented because of cost savings.

http://www.computersociety.it/wp-con...c653_final.pdf
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Old 25th May 2011, 03:20
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Does anyone know if an approach to stall was ever demonstrated in any FBW version of the Airbus while in Alternate law and with invalid ADR input to the the computers? (Please read this question in an AF447 context)

Judging from the X-31 example, one might want to be seated in an ejection seat while demonstrating that point.

If Friday's presentation does include a pitch up into a stall (as has been leaked), did it occur at a speed higher than actual Vstall for the configuration?? If so, AB will have some issues to deal with as well as AF.
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Old 25th May 2011, 03:51
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I've been told by someone involved with the AOA program years ago that only AA and DL have ordered that option in the U.S. What carriers have you seen have the AOA gauge on the PFD and/or HUD?
misd-agin: (& BOAC)

Waving the white flag here.

You are correct. Only “some” 737 NG’s have dedicated AOA displays. I am sincerely trying to avoid A versus B and just present facts.

However, any 737 NG with a HUD has, for all practical purposes, inertial AOA displayed.

FPV’s displayed on the PFD also provide some semblance of AOA. However, the A330 FPV in the FPA/TRK mode possibly disappears below the lower white line on the PFD attitude display at high AOA, possibly without any feedback to the pilot as to un-displayed FPA.

NG HUD FPV “ghosts” when non-conformal at high AOA, and NG’s equipped with the analog/digital AOA display have just that much more information available to recognize very high AOA conditions and correlate that info with other displays.

True, it is a customer option.
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Old 25th May 2011, 04:18
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Software doesn’t deteriorate with age: it is either correct or incorrect but faults can remain dormant for long periods. Ada is very much alive and well. I find it considerably amusing to read posts where the author assumes Ada to be a stale dinosaur - they seem to be quite far removed from reality. We use Ada for commercial projects achieving superior results in comparison with other languages - fewer bugs reach binary, easier to maintain code, certified and tested compilers, self documenting, and standards that read with legal precision... to name a few benefits.
How often have I heard, over the course of my so-called "career" as a "professional", this tired refrain?

There are bodies on the sea floor as we speak, that were put there by over-reliance on automation and plain, irreducible cheapness - the corporate mentality, the idea that ideas themselves are real, and that humans need to be removed from the loop. Fault tolerance - my a__.

228 humans have been permanently removed from the loop.
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Old 25th May 2011, 04:23
  #2329 (permalink)  
 
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OK465, inertial AOA, speed. and all that is fine in more or less still air or air that is moving horizontally - as happens "99.44%" of the time. When there is an updraft the real AOA may be somewhat different from what is indicated. And when we're speaking of single digit degrees that difference could be significant. It'd be nice to invent a real "relative to the air mass" speed and AOA measurement system. Speed's been done. AOA is an interesting problem.
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Old 25th May 2011, 04:33
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When there is an updraft the real AOA may be somewhat different from what is indicated. And when we're speaking of single digit degrees that difference could be significant. It'd be nice to invent a real "relative to the air mass" speed and AOA measurement system. Speed's been done. AOA is an interesting problem.
This has nothing whatsoever to do with maintaining a stable flight configuration while cruising at Mach 0.8.
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Old 25th May 2011, 04:34
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deSitter, they might be considered to have killed themselves because of overreliance on air transportation. (If you can be crass I can trump you. If you think the programmers, designers, and everybody else involved with getting that plane into the air is not unset and feeling terrible about this accident you do not understand people very well. Programmers are people, too. And there are times we flat out TELL management there's no way in hell we're going to do what they want simply because it might have a significant probability of killing somebody when it shouldn't. Er we did some GBU-xx work in our facility. I was briefly involved in some of it. I could not handle the images that conjured. It was too close to real killing rather than communicating. I can argue that my work saved soldier's lives while they dealt with people killing me. Making the electronics in a guided bomb was just too much. We feel, too. And THAT is one of the reasons I support the military demands for Ada based software.)

So let's get real, OK. I used to be a company troubleshooter who got shoveled into situations where we had problems. I watched a high percentage of the programs that went through our facility. I was singularly impressed that I was never needed, never called in, for the Ada programs. Everything else, PL1, FORTRAN, C, Assembler*, and others needed me.

* several CPUs, usually to add features to something old.

Ada is more reliable. But, there is absolutely no way to make any human activity, even sitting on the potty and defecating, 100% safe under all conditions.
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Old 25th May 2011, 04:49
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Is that what you think my point is? I don't care what your choice of weapon is, the issue here is computerization for its own sake, of automation in the name of replacing the human spirit - the one that used to carry flight bags full of approach plates and flashlights and candy bars. My bus - Landbus (TM) driver has more authority over his craft than the person who flies me to Tahiti. This isn't about this tool or that, it's about the obsession with automation for its own sake, how it has become an end in itself. The old hands know what I mean. My motorcycle and I have an understanding.

I should also add, that one does not see a similar obsession with automation where it might matter, that is, on runways and taxiways crowded with Cheapbus RJs stewarded (can I say that word now?) by overworked ATC personnel. Why? Because there is no profit in it.

Last edited by deSitter; 25th May 2011 at 05:20.
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Old 25th May 2011, 05:25
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I don't know about automation for its own sake, but I was amazed when I learned that the airlines were using autothrottles (in whichever form you wish to call it) to manage power during cruise, which ought to be the least demanding area of flight. Do you really want to give a crew so little to do that they have resort to reading books to stay awake? Whatever happened to setting XX pounds/hour per engine fuel flow or YY EPR and then backing it off as required to hold your cruise mach. Do you really save that much fuel?

When you leave the crew so far out of the loop in the actual flying of the aircraft, can you really blame them if they have trouble coming up to speed in an emergency?

OK, yes, I'm a dinosaur. I sometimes used autothrottles (technically an approach power compensator) to manage engine power while flying my swept wing bird aboard ship at night when you can use all the help you can get. But using it in cruise??
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Old 25th May 2011, 05:43
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What? You need help in a night carrier landing? What sort of pilot are you? Just call the ball or shut up and..
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Old 25th May 2011, 05:45
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Testability

Machinbird @ #2321

Judging from the X-31 example, one might want to be seated in an ejection seat while demonstrating that point.
To avoid the costs of ejection seats (or capsule) and destructive testing of the a/c why not to test in the same flights an augmented "APU" turbine? With a 45° rotating nozzle if necessary?

Back to uncensored mode:

Question:

A minimum of how many kN, for this class of a/c, would be required to play a "recovery from stall"? And for generic "unusual attitudes"? (using a 45° nozzle)

Last edited by Jetdriver; 25th May 2011 at 23:20.
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Old 25th May 2011, 06:07
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deSitter; Very simply, were there no accidents before computers were introduced into aviation?

The impeccable reliability of safety-critical computing has most likely lulled people into a false sense of security. Many accidents just wouldn't happen if there were a sober acknowledgment and balanced processing of the general risks associated with flight.

Mankind continues to push the flight envelope further, soon we will be routinely flying manned sub-orbital craft around the planet, which in itself is hardly a bad thing. Computers have enabled progess. But are passengers really aware (at a concious level) that they are paying to travel at near 800km/hr at -50C temperatures, through potentially hazardous weather, and in the dark?

AF could have eliminated the hazardous weather, and darkness risk factors, sacrificing schedules and incurring the cost of an AOG. A few days late, but so what? Passengers would still be alive?! Is it mankind's impatience, his disregard for the fury of the environment, is this our real culprit?
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Old 25th May 2011, 06:10
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deSitter

More automation = more dangerous, is that your point?

Take a look at page 21 of this Boeing document, then please shut up.

http://www.boeing.com/news/techissues/pdf/statsum.pdf
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Old 25th May 2011, 06:24
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deSitter; Very simply, were there no accidents before computers were introduced into aviation?
Egads, I stand convicted. Let's get rid of pilots altogether, those accidents-waiting-to-happen! Vive le telechargement!
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Old 25th May 2011, 06:52
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There are two problems with unreliable airspeed:
1. The unreliable airpeed per se.
2. The bigger problem is when the system (and the pilot) does not recognise that the airspeed is unreliable - and automation then insidiously takes the aircraft closer to the edge of the flight envelope.

Although the system obviously works most of the time, there is a weakness if the system uses 3 identical tubes to detect a problem. If the problem effects all 3 equally, then it can be missed. It will be unreliable, but not recognised as unreliable. Just as three 2nd graders can't together do 6th grade math, 3 problem tubes can't reliably determine airspeed (nor even the state of unreliable airspeed).

With pitot tubes, you are using air flow through the tube to create a pressure, which you then compensate for altitude by using static sensors, and then converting this compensated pressure back into flow (or airspeed). There are a lot of links in this chain. Even worse, a problem could generate either an over-speed (eg blocked pitot drain hole) or an under-speed (blocked tube).

When it is difficult to measure something important, an alternative that is easy to measure becomes important. And so it was 200-300 years ago - flow was difficult to measure, pressure was easy, and so we calculated flow from pressure.

Maybe the time has come for us to measure flow, and thus airspeed directly. Presumably that is the principle behind the [email protected] systems currently being developed.

It may be that pitot tubes today are dinosaurs looking for a tar pit.
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Old 25th May 2011, 07:16
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You are correct. Only “some” 737 NG’s have dedicated AOA displays. I am sincerely trying to avoid A versus B and just present facts.

However, any 737 NG with a HUD has, for all practical purposes, inertial AOA displayed.
...
True, it is a customer option.
The concept of having safety enabling features as "customer option" is somewhat scary. Assume an accident happen and the accident investigation finds out that "lack of AOA information to pilots contributed significantly to the cause". Should the blame fall into the airline beancounters who saved by skipping an "unnecessary option". Or the airplane maker, whose business model includes making extra profit with optional features?

To get back to AF447, the Air France beancounters were reluctant to upgrade pitot tubes to safer ones. I have no idea what the price of the pitot upgrade was, but probably it was not cheap, since it got beancounters on their toes. Blame beancounters? Well, the other side of the coin is that Airbus/Thales was making a profit on what was essentially a safety fix...
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