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AF 447 Search to resume (part2)

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AF 447 Search to resume (part2)

Old 3rd May 2011, 22:40
  #621 (permalink)  
 
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When hit sea surface, INTACT

NeoFit,

In my sense, it's not possible to see an heading value of the plane when impacting water.
If you have an in flight breakup may be would be able to "recover" it´s trajectory.
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Old 3rd May 2011, 22:46
  #622 (permalink)  
 
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#572. BEA is listening.

They heard me. They have set the "Press Release & Information Points for all daily releases back to French being the first URL link.

Sea Search Operations, phase 5

National pride is restored once again!
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Old 3rd May 2011, 22:53
  #623 (permalink)  
 
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unmanned transport,
"Just an idea.
A roll of dayglo orange tape, say 50 feet long should be attached to the CVR and FDR so that it will unfurl and make them easier to find."


I think it's an excellent idea, and you are not the first one on the various AF447 threads to suggest it. And neither was I...
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Old 3rd May 2011, 22:57
  #624 (permalink)  
 
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bearfoil,
"The direction of the nose as the a/c impacted is random, undirected, and most definitely not commanded."

Your description of the flight of an aeroplane that has lost all directional stability is a neat one, and consistent with your hypothesis of the entire fin being lost in flight; unlike the residual stumps of the JAL B747SP, or the B52 in the video link posted by RR NDB above.
No ambiguity there.

To continue the discussion hypothetically, let me suggest the possibility that having read successfully the FDR, under the noses of foreign experts the BEA may announce in due course that any recorded sideslip, up to the moment of impact, is not sufficient to be consistent with the absence of the fin, and that the rudder position parameter is available and valid throughout?
In that event, however surprising it might seem, would you accept the validity of the evidence?
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Old 3rd May 2011, 23:02
  #625 (permalink)  
 
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Originally Posted by RR_NDB View Post
I remember Michel Asseline of Habsheim 320
Here we go again... *sigh*.

I'm sure he's a decent man, but on that day his lack of attention to detail destroyed a million-dollar aircraft and killed three* people. There's nothing else to be said.

This thread is about AF447, not AA587 or AF296. It's about details that we currently don't know, but will hopefully be salvaged from the FDR and CVR. It is not about bashing the French investigators (who have deservedly overcome the bad press that followed them through the 80s and 90s), whispering surreptitiously about composite empennage lugs (that nevertheless held on considerably past their ultimate design load) or a conspiracy by Airbus Industrie to de-skill the profession of airline pilot (an argument I'd like to see the doubters on here have with A320 Captain Chesley Sullenberger).

[* - h/t ARZ]

Last edited by DozyWannabe; 4th May 2011 at 14:41.
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Old 3rd May 2011, 23:14
  #626 (permalink)  
 
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A roll of dayglo orange tape, say 50 feet long should be attached to the CVR and FDR so that it will unfurl and make them easier to find."

I think it's an excellent idea, and you are not the first one on the various AF447 threads to suggest it. And neither was I...
I wonder if tapes might, for example, impede the recorders escaping the fuselage (by snagging on things) where they might otherwise escape & hence make them more susceptible to fire damage? It's such an obvious idea, I kind of wonder if they haven't already considered and rejected it for some other reason?
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Old 3rd May 2011, 23:20
  #627 (permalink)  
 
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Bearfoil Quote:
Why again is the DFDR inside the fuselage and not the Vertical Stabiliser ??
Don't they (VS) have a habit of falling off in flight ?
Recorder in VS would be bad for a simple reason:
Unless you can guarantee that it will stay attached under all conditions (proveably unlikely) you risk a worst case scenario of the recorder hanging on to the -floating- VS for a day or two and dropping into the deep at a location totally unrelated to the rest of the debris field.

In the AF477 case that would likely have resulted in never finding the recorders.
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Old 3rd May 2011, 23:25
  #628 (permalink)  
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Chris

I am unsure the authority of the VS v/v Directional Stability at fifty knots forward, and 160 down. I am not persuaded that the VS would have made a difference at these conditions, whether on or off. You picture me as fixated, and that's fine, but I have not rejected any possibility. You, like most, see an adamant argument, and think it obsessive. At the very least, you take offense and immediately know all other possibilities are bunk, to this person. You are of course wrong. No one knows what happened. Not yet, and until the findings are sussed and confirmed, it is at least as illogical to reject a theory as to embrace its corollary. Objectivity can wear a tuxedo, or a shopcoat. Until BEA abandoned its jargon that described their very own opinion as bunk, and to this day, people picture this a/c as somehow in control and dogged by bad luck. That is the puffery of a partisan, or his "Friends".

I am a follower of Murphy, but did he not also understand sarcasm??
 
Old 3rd May 2011, 23:48
  #629 (permalink)  
 
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"ligne de vol" = "level attitude" (and nothing more)

As HazelNuts rightly points out, there was extensive discussion of this phrase in Part 1 of this thread (back in early July 2010).

For anyone who has not seen that discussion I suggest a quick look at these posts:

#3300 (8 July page 165) NOTanAM

#3301 (8 July page 166) Lemurian

#2808 (3 July page 141) Lemurian

(And thanks to all the regular, expert, posters for such an interesting thread).
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Old 3rd May 2011, 23:53
  #630 (permalink)  
 
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Murphy´s law never fail so let´s go to REDUNDANCY

MurphyWasRight

Considering this fact and LOW COST CHIPS i "propose":

1) Multi CVR/FDR (combi) at wing tips, VS, before and after "aft pressure bulkhead" and in other strategic locations (perhaps, at LDG´s)
2) Use batteries to avoid becoming useless after a complete electrical failure in the aircraft.
3) Improve their capability to be located (pingers, special ELT, ressonant transducer, etc.)

Real time data streaming (telemetry) IMO does not seem practical for many reasons.


PS

Instead of just one ribbon, better to use many shorter ones. The long one can be entangled and later buried underneath a big part rendering a pinger or special ELT, "mute".
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Old 3rd May 2011, 23:55
  #631 (permalink)  
 
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auraflyer, quote:
"I wonder if tapes might, for example, impede the recorders escaping the fuselage (by snagging on things) where they might otherwise escape & hence make them more susceptible to fire damage? It's such an obvious idea, I kind of wonder if they haven't already considered and rejected it for some other reason?"

I also wondered. It would have to be capable of breaking off in extremis, but wrapped so neatly that it was unlikely to catch on anything. So how would it then deploy?
If detached, it could end up anywhere and would be quite a red-herring (sorree), but worse problems than that have dogged this search...
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Old 4th May 2011, 00:58
  #632 (permalink)  
 
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Of course in this case, orange tapes might have saved a few days after the wreckage was located, but wouldn't have helped find it in the first place.
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Old 4th May 2011, 02:21
  #633 (permalink)  
 
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"ligne de vol" = "level attitude" (and nothing more)

MJC2,

Coul you indicate the links (url) of:

#3300 (8 July page 165) NOTanAM

#3301 (8 July page 166) Lemurian

#2808 (3 July page 141) Lemurian
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Old 4th May 2011, 02:23
  #634 (permalink)  
 
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I also think future FDR/CVR installations should be distributed. Engines always seem to be found easily because of their mass, I would think burying one pair of the units in each engine where it is secure, and armored, would be a good idea.

Another pair should be in a floatable buoy.

I suspect certificating entities will have to mandate it before it is done...
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Old 4th May 2011, 02:57
  #635 (permalink)  
 
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The links provided by MJC2 are:-

AF447 #2808 p141
AF447 #3300 p165
AF447 #3301 p166

With regard to Lemurian's post #3301, I believe he has laid out the true circumstances of the aircraft's arrival at terra oceania. In the sense that the attitude was nearly level and the vertical rate of descent was high, the matter of direction of travel (or speed for that matter) was virtually irrelevant. Though, as HazelNuts39 has reiterated, the BEA did modify its stance on the "en ligne de vol" in its preliminary Report No.2.
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Old 4th May 2011, 03:01
  #636 (permalink)  
 
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Distributed recorders (redundant)

Khashoggi,

Indeed, engines are more "locateable" than a tiny "free" CSMU.

Just one recorder can be enough for Data and AUDIO.

The info is the same: BITS.

The AUDIO recording is the same thing of DATA recording.

The era of Audio (analog) and DATA separated is gone.

So the cost also. (Dropped)

There is room for improvement. This case will help for changes.

2 years + waiting for a result (analysis and recomendations) of this magnitude is IMHO an ABSURD

Unfortunately the Regulatory, etc. entities are not proactive. They trail the crashes. Managed by bureaucrats.

And the "technical people" has not the tools for the "decision making"
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Old 4th May 2011, 03:08
  #637 (permalink)  
 
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Links

mm43,

Will read ASAP.

When we comment unfortunately in most of cases we have no time to read everything was posted. When searching for the links i also found multiple threads on this issue.
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Old 4th May 2011, 03:53
  #638 (permalink)  
 
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Recorder Locations

1. The recorders are placed where they are least likely to be damaged in the typical crash. Of all the crashes in the jet age, only a handful have been into deep water.

2. The recorders may be used only once or twice in the lifetime of the airframe, if at all. The rest of the time they are dead weight. They may be used for FOQA, etc., but that is not primary purpose.

3. The recorders are certified with the airframe. Subsequent moving to another location would cost heaps of money, with little probability of return.

4. The recorders should be in a benign environment. That precludes mounting with the engine. The A330 FDR outside the pressure vessel is hardly benign, either.

5. The power to the recorders must be as secure as possible.
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Old 4th May 2011, 04:23
  #639 (permalink)  
 
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Recorder Locations (distributed memories)

Graybeard,

1) One of the least likely places to be damaged in most crashes is in the tip of VS. You can put one of tiny recorder there (actually the memory unit). I am not speaking of the currently available recorders. A new generation. Not a big R&D.

2) Can be light and cost effective. (only the memories to be redundant)

3) No problem

4) I would not say "precludes". Better to say, must take into account engines environment. I don´t see this as a big problem.

5) Redundant power (DC coming fro a/c and internal battery). An optimized design can be feed by Li ion easily for adequate time. No problem.

Ok, there are EMI/EMC considerations, costs, etc., etc. My point is, the current solutions should be improved.
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Old 4th May 2011, 06:16
  #640 (permalink)  
 
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No power, no data

2) Use batteries to avoid becoming useless after a complete electrical failure in the aircraft.
And what would the recorders record after a complete electrical failure?
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