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-   -   AF 447 Search to resume (part2) (https://www.pprune.org/tech-log/449639-af-447-search-resume-part2.html)

PJ2 1st May 2011 22:47

mm43;

but suspect that even if water has penetrated under pressure, that the individual chips will still give up their contents when interrogated
I was wondering that - so the "substrate" of the chips, (with the 'real' works inside the substrate, so to speak) would likely protect the memory and the memory itself would be readable? (given that it is otherwise intact)

glad rag 1st May 2011 22:54

What is required is a cross section of the unit, but I think Honeywell may have something to say about that!!:ouch:

bearfoil 1st May 2011 23:09

jcj

I for one agree with you. The principals were "done" after Phase two, certainly after Phase Three. It cannot be proven unless a civil suit is initiated by the families implicating the two private corporations, and the BEA. "No Harm no Foul". Had the families and their advocates not insisted, there would be no "recovery". It is not through the heroism of AF or AB, that is absurd. The independent crews and professionals are the achievers, but again, only because there was impetus from families, and the Court, with its indictment of manslaughter.

Having a bias whilst in a position of authority is as prevalent as air. Objectivity is the target, but the bull is seldom pierced. Accusing of a bias is not a Conspiracy. A conspiracy is a secret discussion of a plan that is unlawful. The conversation is in and of itself a crime. Too many posters here are puffing nonsense without an understanding of the language.

A "theorist" is not to be scolded, however, as PJ2 declares, absent a reasonable demonstration of possibility, one holds a theory loosely.

This thread is the most fun I've had since I quit flying. And fun to me is confrontational dialogue; since I have learned a great deal, there's the grail. (for me)

If 447 started going down at 0210, and the wreckage is within six miles, she had an average rate of descent of over 6,000fpm at 45+ degrees ND ??

jcjeant 1st May 2011 23:13

Hi,

FDR finally found, was a milestone in the investigation.
Another highlight (but this time on the FDR himself) is that the pinger is no longer attached
I hope they still look as it is also important to know whether pinger (s) was in operating condition during the first 30 days ......
Again we see that the design does not meet expectations
So there's already a lesson to learn (although this is not a first .. so it's a nail hammering !) ... and especially of the responses made to perfect this device ....

SaturnV 1st May 2011 23:13

The procedure, announced in advance, is that a French naval ship will transport the recorder back to a French port, and from the port it will be flown to Paris. The recorder is now in the custody of the French Judicial Police, and will remain so until it is examined by the BEA in Paris.

My reading is that the port is a continental port.

auraflyer 1st May 2011 23:28

One thought about the FDR that has been bugging me for a while:

if there was unreliable data in the system (not least, airspeed) won't this incorrect data be contained in the recorder? Are there enough other parameters recorded that could be used to work out the actual values of suspect values, if at least some of what is recorded is affected by defective inputs?

mm43 1st May 2011 23:32

PJ2

... so the "substrate" of the chips, (with the 'real' works inside the substrate, so to speak) would likely protect the memory and the memory itself would be readable? (given that it is otherwise intact)
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.

bearfoil 1st May 2011 23:34

auraflyer

no worries. It's all in there, and if the CVR works, there will be some expert commentary to go along with the traces. The grail is home.

RR_NDB 1st May 2011 23:37

Readability of recovered CSMU
 
In the FDR wewbsite we have:

http://www51.honeywell.com/aero/common/documents/Flight_Data_Recorder_%28SSFDR%29.pdf


In page 9 you can see the kind of protection to the PCB where the FLASH MEMORIES are soldered.

This protection is the first layer.

If the PCB is corroded an alternative is RESOLDER the ICīs in another PCB.

A third alternative would be read the content of each chip in the manufacturer.

IMO the chances to READ ALL DATA are high.

Finger crossing.

PS

We can suppose the new cylindrical shape is more survivable than the one showed in the product link. The former seems very tight.

We learned they are using the cylindrical shape as observed by Nick L at Post #424:


The drawing on the Honeywell data sheet is not correct for the "4X" (4700) series recorders. It is only correct for "1X" and "2X" models.

MountainWest 1st May 2011 23:46

FDR Damage
 
The FDR appears to be damaged (IMHO) far more than can be explained by a 100g impact. It was designed and located in the aircraft in the best position to maximize survivability in a high-speed forward impact. On its face, this device experienced miniscule forces compared to what it was designed to withstand.
That said, perhaps what we see is evidence of the FDR being caught between major structural components at the time of impact. Did VS attachment hardware (or a similar event) crush the FDR and pinger against a major structural component on departure from the aircraft?

auraflyer 1st May 2011 23:46


no worries. It's all in there, and if the CVR works, there will be some expert commentary to go along with the traces.
Just reflecting on some of my past encounters with the old GIGO (garbage in, garbage out) problem -- first order of business was working out which are your "known good" or "suspected good" values, which you had to use to identify/(correct if possible) the "potentially bad" ones ...

Also, while there's "pie in the sky" talk about their design, I wonder if there's any ability to have some redundancy between the recorders -- in addition to what the CVR currently stores, is it possible to have it record at least some of the key FDR values, and vice versa (if that is possible). I suspect cost/size would come into play though...

macilrae 1st May 2011 23:51

Accelerometer
 
I find the fact that there's an accelerometer included in the data recorder package most fascinating (the Honeywell pdf says it's an option but I assume it's there). With this, of course, the complete terminal trajectory of the aircraft (or at least the portion containing the recorder) can be reconstructed up until the unit lost power - even continuing until the memory unit separated from the chassis in theory.

RR_NDB 1st May 2011 23:54

Before and after UAS
 
auraflyer

The chances to UNDERSTAND everything with readable FDR and CVR are near 100%.

Remember you are continuously recording before and after the "air speedometer"
fails. This fact,the number of parameters you can analyze, their timing together with AUDIO recorded in cockpit from many sources (microphones) allows a very complete analysis. Fascinating, indeed.

Very probably we will be able to Xcheck with ACARS because electrical supply to the recorders may be lost only at sea surface impact.

Machinbird 1st May 2011 23:55

Regarding the concern over the circumferential line on the end of the memory unit. Remember, there has to be a way into the unit to build it and service components. Most likely we are seeing an end plug with O-rings that seal the actual aperture into the casing. The other end seems to have a ribbon cable coming out of it in one of the pictures. The condition of the ribbon cable looked quite good.

mm43 1st May 2011 23:55

France24 - AFP report
 

"The investigation team has located and identified the memory module of the Flight Data Recorder (FDR) - at 10H UTC (GMT) this morning (Sunday morning). It was back aboard the ship (Ile de Sein) at 16:40 UTC (ie 6:40 p.m. Paris time), announced the Bureau of Investigation and Analysis (BEA), responsible for technical investigation.

"At this stage, the box looks in good physical condition. Our experts tell us that we can hope to read that data, " Jean-Paul Troadec told AFP.

He however expressed caution noting that for the moment, it was unclear whether the case had been damaged by corrosion.
Note the BEA's caution!

auraflyer 2nd May 2011 00:00

Thanks Mac.

My fault - I didn't make it clear that I was wondering about a situation where they only recover FDR, but no CVR. Need my morning coffee ... :)

RR_NDB 2nd May 2011 00:08

Optional accelerometer
 
macilrae,

I didnīt see mention to the optional accelerometer at BEA info.

Itīs offered in page 10 of:

http://www51.honeywell.com/aero/comm...28SSFDR%29.pdf

This data are fed by a/c sensors and Systems like INS i guess.

Chris Scott 2nd May 2011 00:32

bearfoil, quote:
"This thread is the most fun
I've had since I quit flying. And fun to me is
confrontational dialogue."

Ouch!

"Too many posters here are puffing nonsense without an understanding of the language."

Quite. :rolleyes:
bearfoil, this thread wouldn't be quite the same without you! Just hope you didn't create as much confusion in the cockpit as you do routinely on this thread...

"A "theorist" is not to be scolded, however, as PJ2 declares, absent a reasonable demonstration of possibility, one holds a theory loosely."

Huh? Oh well, never mind... :confused:

On a more serious note:
"If 447 started going down at 0210, and the wreckage is within six miles, she had an average rate of descent of over 6,000fpm at 45+ degrees ND ??"

To descend about 37000 ft from FL350 in a straight line would be slightly over 45 deg flight-path angle, assuming the dense debris is within 6 (nautical?) miles of LKP. Seems impossible unless the aircraft was already stalling at 0210z, which would surprise some of us. But there is also the possibility of a high-speed diving teardrop, followed by a stall at low altitude.

Few of our various cherished theories are going to survive the FDR traces...

Old Carthusian 2nd May 2011 00:32

Bearfoil

Of course BEA, Air France and AB were going to try and find the wreckage come what may. The simple reason for this was they didn't know what happened and not knowing means that there could be a reaccurence. Knowing what happens means that they have a possibility of avoiding this reaccurence. There was never any question of them abandoning the search until they had found the aircraft. Pressure from families and other bodies was a side issue. The French authorities have done an excellent job in finding and recovering the FDR and instead of being churlish about this you should be acknowledging the good work.

Centrosphere 2nd May 2011 00:42

mm43,


"Ile de Sein" departed from Dakar, Senegal for her voyage to the Recovery Operation Position (ROP).
Actually youīre right. I made a confusion; it was the Alucia that took three days from Recife to the place where it began the previous search.

What really matters to my calculations is that a ship can take 3 days to reach the brazilian port of Recife. But, as someone already said, the equipment will be sent to a French port before a plane take it to Paris. A desnecessary delay, one could say, but I understand that the french wants everything into their jurisdiction.


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