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Old 29th Apr 2011, 02:20   #301 (permalink)
 
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"sometimes a cigar is just a cigar". Monica would not agree with that statement but it is unfortunate that conspiracists would likely also say the moon shots were fake so reject these superb examples as well. Could the damage also be from water entering the tail during "touchdown" when the tail fin mounts/support ribs were deformed and the plane was still 'moving forward dragging the tail'. ie the tail ribs were bent backwards from memory indicating possibly a large 'wave' of water entering the tail from the front. FF
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Old 29th Apr 2011, 02:52   #302 (permalink)
 
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Cool

Hi,

The find of the pingers will be also interesting.
As now we know that they are certainly in the (or around) the debris field .. this was at the time of the acoustic researches (results negative) no environemental constraints (other than the water depth) as mountains or crevices reducing the field of emission
So it will be interesting to know if they had some malfunctions
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Old 29th Apr 2011, 03:47   #303 (permalink)
 
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Quote:
AlphaZuluRomeo (Regarding where to look for the memory unit)
Indeed I haven't seen the "wreckage distribution and how it had been influenced by a slow moving current from E to W" theories as a fact.
I was under the impression those they looked a little too much like a "guesswork", based on a single sonar picture without proved link between significant parts and the said sonar image, to pay attention to them
Were you perhaps waiting for Professor Einstein to visit the crash site and formulate a formal theory? For many reasons, that won't happen.
Thinking men look at data and form theories regarding the underlying factors at work. Others look at the theory and point out weak concepts, and the theory is adjusted to improve its fit to the observed data. Just because a theory has not been examined by a formal board of scientists does not mean it is without value. A plan based on underlying theories is actionable. Worst case, you will gain better data to adjust the theory further. Without a plan, you are just a lost kid waiting for your mother to lead you back home.
Without better information regarding the factors distributing the wreckage, I would look East of the FDR chassis for the memory module, against the apparent current that distributed the wreckage. With an accurate wreckage map and hydrodynamic drag data for the FDR chassis and memory unit from the manufacturer, it would not be guesswork to locate the memory module. Not even a SWAG.
Both of these units started their trip to the bottom from the same initial location near the surface. Unless one became entrapped by another part, they will fall as gravity and ocean currents direct them.
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Old 29th Apr 2011, 03:58   #304 (permalink)
 
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Quote:
Originally posted by lomapaseo ...

I once bought a 5 lb magnet for the sole purpose of recovering objects like this from the mud
Long way to the shop.

Suspect they'll butcher a loudspeaker or two for permanent magnets should all else fail.
Quote:
Originally posted by Machinbird ...

I would look East of the FDR chassis for the memory module, against the apparent current that distributed the wreckage.
So would I, but then neither of us are going to influence the outcome.
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Old 29th Apr 2011, 04:32   #305 (permalink)
 
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deSitter,

"Just to put this to bed, here is what happens when you get moon dust on a lens at f/16."

Iīm afraid youīre quite wrong. The effect in these NASA pictures is more probably due to "blooming":

"Blooming
Techniques > Glossary > Blooming

Streaks or halos appearing around bright areas of an image that are caused by gross overexposure to the CCD. It's like an electronic equivalent of flare.
"

Mutatis mutandis, also overexposure of the filmīs emulsion. Thatīs clearly the case at NASA pictures and clearly NOT the case at the ROVīs picture since the central region is actually darker than the surroundings.

Yep, I know that these moon photos have frequented a lot of conspiracy sites. I know also that the "dust" explanation was first presented by NASA itself (tentatively), so youīre not being original. This explanation carries some power, since we know that the Moonīs dust is very sticky due to being electrically charged. Actually, it took some time until the comprehension that dust has a complex cycle on Moonīs surface landed at NASAīs astrophysicists minds _ even some nominally open-minded scientists can have trouble in recognizing the unexpected, see?

By now, Iīm gradually coming to terms with the funny fact that the bigger conspiracy theory here at this forum is that one built by some members to call other people conspiracy theorists, no matter how these people shout they arenīt. This is a little bit sad, but unfortunately, well inside the known range of human stupidity.
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Old 29th Apr 2011, 04:39   #306 (permalink)
 
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MM43

You must be making the comment "tongue in cheek" magnets as you know will erase the memory chip caboolture
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Old 29th Apr 2011, 04:52   #307 (permalink)
 
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Look Centrosphere, you should be around long enough before you start correcting people and implying that they don't know what they are saying. I started doing black and white darkroom photography centuries ago, I'm an amateur astronomer, I know how photography and optics work. This is not blooming - it's a normal exposure, most likely 1/250th second at f/16 or f/22, onto a special Kodak 70mm thin emulsion specifically designed to minimize unwanted artifacts - it's dirt on the lens, "dirt dirt" as Pete Conrad called it.
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Old 29th Apr 2011, 05:03   #308 (permalink)
 
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Where is the CSMU

1) Likely separated from yet located rack just after a/c surface crash
2) Due geometry and weight i guess in grater chances to be near tail parts of similar weight and compatible geometry. (similar geometry?)
3) Buried? Difficult to say!
4) East or West to rack? Use K.I.S.S. approach (Keep It Simple, Stupid)
The one that made Kelly Johnson put an Angel to the skies, flying near
the coffin corner in just 80 days. The legendary U2.
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Old 29th Apr 2011, 05:08   #309 (permalink)
 
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Both of you JCL's are wrong.

Astronauts Neil Armstrong, Michael Collins & Buzz Aldrin talk about UFOs
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Old 29th Apr 2011, 05:13   #310 (permalink)
 
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I stand corrected I have to stand because by empennage hurts after what they did to me.
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Old 29th Apr 2011, 05:47   #311 (permalink)
 
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Quote:
Originally posted by Machinbird ...
I would look East of the FDR chassis for the memory module, against the apparent current that distributed the wreckage.
Quote:
MM43
So would I, but then neither of us are going to influence the outcome.
You mean to say that BEA hasn't learned to come to PPRuNe for hints?
Darn! I thought they had better sense than that, particularly after their prior search troubles.
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Old 29th Apr 2011, 06:25   #312 (permalink)
 
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caboolture;
Quote:
You must be making the comment "tongue in cheek" magnets as you know will erase the memory chip
Was kind of hoping that the CSMU is using "flash" memory, i.e. electric field and not magnetic field to change data state. A permanent magnet shouldn't have any effect.

A low frequency tuned inductive loop could also be used for detecting a buried steel object. The oscillator frequency would "dip" if a ferrous object intersected its field. A bit like "treasure hunting".

Last edited by mm43; 29th Apr 2011 at 06:42. Reason: spelling!
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Old 29th Apr 2011, 06:35   #313 (permalink)
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Machinbird;

Good post on "speculation" etc. I think it is entirely reasonable to use available information to form theories from knowledge and experience, but the basis for theory must be there for all to see and where disagreement arises, the facts must be available to demonstrate same.

The BEA 2nd Interim Report states that AF447 had a Honeywell SSFDR 980-4700-42. Information on this recorder may be easily found on the web using standard search techniques. It may help with a few details. The link can't be posted because it is commercial material. The SSFDR weighs about 13 lbs and is mounted between frames 84 & 85 very close to the bottom of the airframe.

mm43;
Quote:
I've puzzled about how the CSMU/ULB departed, and the only explanation I can come up with is:-

The 'g' forces at impact were complex, and the initial underside impact caused the the whole SSFDR to be punched up, and at the same time the mass of the CSMU tried to continue forward and to port, resulting in the securing bolts pulling then shearing off.

Perhaps a further look at the V/S clevis joints damage may help explain it.
That doesn't give a satisfactory explanation as to why the CSMU/ULB left its mount before the SSFDR, unless the tensile strength of the CSMU bolts were less than those of the SSFDR securing bolts.
I think that is a very reasonable description. I think the broken CSMU should not a complete surprise in the circumstances of the impact on a relatively light section of the structure. Loss of the CSMU has occurred once before as has been posted, and been found again so we can expect that it is a matter of time. There will be opportunity in the future to discuss designs and why the separation, (something Honeywell is likely talking about now), but at the moment finding the CSMU is primary, and then reading it.

It may be bolt tensile strength was exceeded or that the bolt-heads may have pulled through the bottom of the casing. Either way, a clear dimpling of the bottom surface can be seen where the bolts were and the casing itself has been stressed sufficiently to bend upwards in a same way that mirrors many other recovered parts in accordance with the impact described in the BEA Interim Reports.

The first place I would be looking would be the tail section and where the tail section lay. The area above the recorder is relatively clear and the pressure bulkhead is just forward and the heavy HS wing box, THS equipment, rudder control equipment and of course the APU, aft of the HS box. The CSMU may very well have shot upwards in the instant of impact into the collapsing framework from below and above.

Anyway, as you say, it's all reasonable speculation but I don't think they're reading here for advice. I look forward to news of finding the CSMU.
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Old 29th Apr 2011, 09:30   #314 (permalink)
 
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Centrosphere

Quote:
"In the middle of the picture both lamps have equal brightness and so each lamp cancels out the shadow cast by the second lamp (unless the feature is big enough so that the lamps create two overlapping shadows). The result is a low contrast area."

Clever explanation, but...why this would only happen at the central region of the image and not along the vertical axis of the photo?
One could argue that in this picture there is in fact a tendency that the off-centrepoint shadows do become deeper when going in the horizontal direction than in the vertical direction. At least I can see no tendency of the opposite effect.

Also: Any offset of the lamp mounts relative to the lens (either in the vertical direction or along the optical axis) would have the effect of introducing off-centrepoint shadows along the vertical axis. This means that the "vanishing shadows" effect weakens along the picture's vertical axis.

Another thing to consider is that according to the spec, the ROV has four searchlights. If all four were lit (assuming they are not mounted on the same horizontal line, and are aimed with converging beams) , the effect would also be that the "vanishing shadows" weakens along the picture's vertical axis.

However, we don't know the specifics of this lighting setup, so this is partly what-if speculation. I'm just trying to point out some possible explanations to what can be observed in the picture.
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Old 29th Apr 2011, 10:01   #315 (permalink)
 
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Machinbird, I meant no offense, sorry if my poor english let you under that impression.

What I wanted to say is:
"wreckage distribution and how it had been influenced by a slow moving current from E to W"
can't that be:
"wreckage distribution and how it had been influenced by a slow moving current from W to E" ?
I guess I'll have to browse back the first topic, I certainly may have missed some information there. Will do that ASAP.

Quote:
Originally Posted by Machinbird View Post
Were you perhaps waiting for Professor Einstein to visit the crash site and formulate a formal theory? For many reasons, that won't happen.
Sure it won't. But I hope the research teams will find & publish the facts & theory in due time. In the mean time, I'm indeed sitting (mostly) still
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Old 29th Apr 2011, 10:28   #316 (permalink)
 
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What about the QAR?

QAR data have been helpful in crash investigations before: Strasbourg for example, where the FDR itself was destroyed by fire, or Gonesse, where the QAR recording medium was more conveniently accessible (optical disc vs. magtape).

The interim report mentions only the CVR and FDR models installed on AF 447 (Honeywell 6022 and 4700, respectively), nothing about the QAR. Does anyone know what kind of device that might have been?
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Old 29th Apr 2011, 10:54   #317 (permalink)
 
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Centrosphere, what you are seeing is compression artifacts. I don't think you can draw any conclusions out of them. I'd personally not cry wolf until I really see one.
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Old 29th Apr 2011, 11:18   #318 (permalink)
 
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mm43, old disk drives often have small but very strong magnets for the head positioning mechanism.
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Old 29th Apr 2011, 11:22   #319 (permalink)
 
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Centrosphere, I believe you will find that the cameras used on the Moon were vidicons, empty state electronics, that are very susceptible to blooming. With CCDs blooming should not be a significant problem compared to what you get with vidicons.

(Somewhere around here I have some vidicon cameras from the 80s. Their blooming is VERY dramatically worse than what I get with the CCD camera I have.)
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Old 29th Apr 2011, 11:25   #320 (permalink)
 
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Caboolture, please say that bit about magnets erasing solid state memory cards, again. I need good laughs from time to time. The memory technology in SSDs does not involve anything more magnetic than what you get with the very very low currents on integrated circuit conductor traces.
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