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AF 447 Search to resume (part2)

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AF 447 Search to resume (part2)

Old 4th May 2011, 18:08
  #681 (permalink)  
 
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Cool

Hi,

Disgression ... relax

I like the 737, less of a noisy flying Coke can than the A320 family, from the SLF point of view.
What better than the "Classic" !

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Old 4th May 2011, 20:26
  #682 (permalink)  
YRP
 
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@ BJ-ENG

It's also interesting that the BEA allowed Honeywell to dig into the electronics. In section 2.4.1 of the EUROCAE document: MINIMUM OPERATIONAL PERFORMANCE SPECIFICATION FOR CRASH PROTECTED AIRBORNE RECORDER SYSTEMS, it states:

NOTE 1: Microscopic examination of the surface characteristics of memory
devices is not acceptable as means of data recovery.

NOTE 2: The repair of individual memory devices is not permitted.......


Seems a rather restrictive policy considering that all measures need to be applied to discover the truth - maybe it's a legal issue...
I suspect that this is a legal statement: the FDR design has to meet the specifications (that you can read out the data after up to 30 days underwater etc) without requiring those techniques. They want the design to be readable through the normal ports. But if for some reason that fails, they will go to any extent required.

I agree with you that there is some risk of exposure to water, however there are a lot of layers of defense: the CSMU casing, presumably some kind of coating on the PCB, the chip package.

In the end, IMHO, they are pretty likely to be able to read it, even if it requires extensive measures like removing the die from the package and using the equivelant of a wafer probe tester to read it out.

@ mm43
That is my understanding, and as a data state change can only occur with an applied voltage, any potential short circuits can be ignored.

I am sure that if the initial download in France fails, the CSMU will be flown to the USA to enable Honeywell to access the substrate and interrogate the chips directly.
You are correct: a flash memory chip requires a programming voltage. It is unlikely to have lost the contents although not impossible.

There are several ways to read the chips out: on the circuit board (not sure I'd try powering it up at this point, at least not without checking it carefully), by removing the memory chips and reading individually, and (at the extreme) removing the chip die from the plastic package and probing the bare die.

I couldn't see any mention in the FDR product description link, but there might be some amount of error correction/redundancy built in (something like storing 2 copies of the data in case one is corrupt, although there are more clever ways to do it). Anyone know if the solid state FDRs do this?
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Old 4th May 2011, 20:57
  #683 (permalink)  
 
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It's also interesting that the BEA allowed Honeywell to dig into the electronics. In section 2.4.1 of the EUROCAE document: MINIMUM OPERATIONAL PERFORMANCE SPECIFICATION FOR CRASH PROTECTED AIRBORNE RECORDER SYSTEMS, it states:

NOTE 1: Microscopic examination of the surface characteristics of memory
devices is not acceptable as means of data recovery.

NOTE 2: The repair of individual memory devices is not permitted.......

Seems a rather restrictive policy considering that all measures need to be applied to discover the truth - maybe it's a legal issue...
I would think this simply is a quote from the qualification/certification documents.
After the 'nominal' environmental tests, you're not allowed to 'demonstrate compliance' re data recovery by taking the data module apart and examining/interrogating the individual memory devices.

Once the 'real world has intervened', any method that can extract the data is only too welcome....

Edit: sorry, hadn't seen YRPs post yet, which says much the same thing.
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Old 4th May 2011, 21:03
  #684 (permalink)  
 
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jcjeant,
Thanks for the (offtopic) video.
Worth watching, I take my hat of to whoever made it....
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Old 4th May 2011, 21:05
  #685 (permalink)  
 
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3holelover;
One shows a fuselage with bits of fin attached, and the other shows a fin with bits of fuselage attached.
Precisely! The only problem we have is that this thread keeps readdressing this issue ad infinitum.

The only relationship between AA587 and AF447 is that they were both Airbus aircraft and used a similar vertical stabilizer design. The first lost its V/S in the air, while AF447 clearly lost it during the course of a high 'g' impact of the aircraft with terra oceania and consequential to the break-up forces produced at that time.

I'm sure that I shouldn't need to repeat that. The BEA have stated that and shown ample evidence of the trauma caused to the clevis joints and the parts of the empennage that came away with the fin. Every other argument in favour of an airborne demise of the fin is doomed to fail, as no-one will be able to conjure up a source for the 'g' forces that could cause the damage so recorded. On the other hand, the damage amply equates to the BEA's description of the impact - further confirmed by more recent photographic evidence.

Now, the above rant is the way I see things, and I am well aware that the conspiracy theorists will see it differently.
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Old 4th May 2011, 21:39
  #686 (permalink)  
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Until a truce is resolved, I will point out there is less evidence for either position than one in the middle. Given patent damage to CFRP tabs whilst airborne (AA587), and a similar though <fail presentation on 447, It is feasible that the VS (447) started to fail whilst airborne at the VS tabs (see photography, these fractures are indicative of side loading). On impact, whatever lateral and torsional stress did in the VS and stressed the hoop/frame joins, impact forces were sufficient to dislodge and toss clear the VS/R. On top of that, the lateral rods failed in the designed for direction. This vector (Lateral, fancy that), is further evidence of a dynamic and unwelcome airload(s). My heels are unstuck, and I suggest it is more comfortable than banging either gong.
 
Old 4th May 2011, 21:48
  #687 (permalink)  
 
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video of recovery

For anyone not also reading the R&N thread, there's a post on there with video / interviews from the recovery vessel:

http://www.pprune.org/rumours-news/4...ml#post6429229

Worth watching, and shows where the BEA photos came from - photos of live ROV video stream showing on the monitors.

That said, I am half sure (might be just imagining it) that there is a central slightly blurred patch in at least one sequence of ROV video (around 10:00). If it's there, it's moving with the ROV viewpoint, could be dirt on the ROV, or lighting effect, or dirt or reflection on the monitor - but doesn't look like it could be post edit of the photo.
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Old 4th May 2011, 21:53
  #688 (permalink)  
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infrequentflyer789

I caught that, and I think BEA, if confronted with a bit of disturbing organics in frame, would simply blank it out. Why risk the abuse of the critics ?? BEA is not Disney, and my thought is they would be direct, and not "shoppish" ??

I think dirt, or some artifact. In the midst of this hallowed site, even bear is reluctant to criticise.....
 
Old 4th May 2011, 22:00
  #689 (permalink)  
 
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Originally Posted by bearfoil
On top of that, the lateral rods failed in the designed for direction.
As explained at length earlier, they didn't. From BEA #2, 1.12.3.5.7 Examination of the fin-to-fuselage attachments:
The centre and aft lateral load pick-up rods showed damage that was consistent with this backwards pivoting of frames 84 to 87:
- tensile failure of the centre spar at the level of the centre rod attachments;
- compression failure of the aft spar at the level of the aft rod attachments and failure of the left-hand rod by buckling
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Old 4th May 2011, 22:12
  #690 (permalink)  
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Hazelnuts39

Understood. BEA conclusions are not exclusive of other stresses. Of all people, in a chaotically dynamic system, one set of stresses is erm...farfetched, no??

Briefly, BEA reports are written "enclosed", or inward. They are not the only ones. Were I to write for this agency, I would write in the same manner. Given somewhat less than complete data, I would compose prose that allowed non-objective and amateurish readers the chance to exclaim to themselves, "That's it, then," "sufficient, no other way."

"Julia, what color is that house??" "White, on the side I can see...."

As odd as it sounds, BEA should "wait for the Final Report".
 
Old 4th May 2011, 22:59
  #691 (permalink)  
 
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Originally Posted by SaturnV View Post
Very long New York Times article on the finding of AF 447.

What Happened to Air France Flight 447? - NYTimes.com
Now that IS journalism.
Well done NYT, and many thanks to SaturnV for posting it.
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Old 4th May 2011, 23:20
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"Julia, what color is that house??" "White, on the side I can see...."
Bear,
Did you study law at some point in your life? The structure of your arguments seems to point in that direction. You sound like a lawyer ready to argue any side of a case that will pay the fee.
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Old 4th May 2011, 23:37
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sound like a lawyer ready to argue any side of a case that will pay the fee.
Or a contrarian automaton with a limited repertoire.
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Old 5th May 2011, 00:01
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Would there be any value in scattering a few extra pingers around the airframe? There'd be no guarantee, of course, that any that worked would end up in the vicinity of the recorders. But even ones far from the recorders would likely be near something worth recovering.
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Old 5th May 2011, 00:10
  #695 (permalink)  
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Machinbird

I won't deny I have written for money. My bias has been stated many times, I want to see the pilots and crew get a fair shake. What can one conclude from my last post, if one could read no other?? I distrust BEA and the Principals, I have worked in their domain. No moral judgment, to see what's real is the goal. BEA have not conclusively eliminated most of the theories here. Those who trust they disclose from a public spirited foundation have a screw(s) loose.

Absent the continuation of the search, Thales, AB, AF and some others would make paltry offers of "wholeness". Depending on the recovery of what actually happened, it is now possible that the principals and even the Government of France will be severely wounded. The Pitots. The pitots were to be replaced, and the pilots (AF< UNION) as much as gave up the answers when they struck. If it was UAS, predominantly, there is cause for billions of dollars to change hands, and some firms will have to reorganize. No one wishes this, unless it is just.

Julia is the TRUTH, and carries the scales. What else can she say but what she 'sees' ??
 
Old 5th May 2011, 01:11
  #696 (permalink)  
 
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Originally Posted by bearfoil
Were Load traces supplied in the report Perpignan??
The load factor played a critical role during the last minute of that flight … but no published data !?
How much the BEA is interested to tell the all story and not only what Airbus gives its blessing on …

That was Perpignan …
Now let’s see which data we’ll be authorized to have a look on AF447 ?
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Old 5th May 2011, 01:35
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I distrust BEA and the Principals,
Yes, you have made that ABUNDANTLY clear. Does repeating it 'ad nauseam' make it more correct?

We all realize the need to be cautious where conflicting interests exist, but do we need to re-state this position every time we speak? I believe BEA will present accurate raw data, but the real potential for bias lies in the interpretation of that data! That which is not said can speak volumes.

the pilots (AF< UNION) as much as gave up the answers when they struck.
I have no reason to believe that the pilot's union has any better information as to the cause of the loss of AF447 than the rest of us do. They saw one area of potential uncertainty and demanded it be corrected, but in reality, there is no assurance (as of the present moment) that the changing of the Pitot tubes could have made any difference in the outcome for AF447.
If AF447 actually pitched up and stalled for another reason-the Perpignan accident indicates we would have seen the same type messages regarding the ADR systems.
Lets just quietly watch events unfold and speak up when things don't look quite right or we do not understand. After waiting almost 2 years for answers, we may see some sooner than we can imagine.
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Old 5th May 2011, 02:12
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CONF iture

"Now let’s see which data we’ll be authorized to have a look on AF447 "

This is the part of the process that is galling. One hopes in a free society for disclosure. Not parses and morsels doled out after editing or prohibition by the ones accused. Non-Disclosure of material that has bearing is a species of Fraud.

France owns a hefty piece of ABI, and the BEA is a division of the Government, how could anything go sour??

Machinbird

"We all realize the need to be cautious where conflicting interests exist, but do we need to re-state this position every time we speak? I believe BEA will present accurate raw data, but the real potential for bias lies in the interpretation of that data! That which is not said can speak volumes."

Having repeated this position ad nauseum (I agree), I still see a lack of scepticism, something that is not healthy for a free people. Critical thinking keeps us alive and prosperous. Signing off on BS encourages the weak links.

I'll give it a rest. Honest.
 
Old 5th May 2011, 02:45
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ChuChu,

Scattering pingers around is quite as likely to create false leads, red herrings, so not likely. Just as installing recorders in the fin seems complicated from the point of view of access - as has been mentioned in this thread.

A concept that seems difficult for people to understand is how technologies race against each other to keep up. The FDR and CVR technologies are sometimes described as "ancien"t but the airframe designers - who accommodate that equipment - need to use existing designs as their starting point. It becomes an issue of how many tails does the dog wag or, how many tails wag the dog.
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Old 5th May 2011, 04:03
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France owns a hefty piece of ABI,
What is ABI?
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