PPRuNe Forums - View Single Post - AF 447 Search to resume (part2)
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Old 2nd May 2011, 12:04
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lomapaseo
 
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BJ-ENG

On a more hopeful note, we know from the interim report that the G forces experienced for the majority of passengers (front to rear of aircraft) was in the range 100 to 200G (from pathology), so it is therefore reasonable to say that the FDR and CVR experience something similar or less, and was then subjected to 400atmos pressure for 2 years. Given that these devices must pass certification at 3400 G (6.5ms) and also be able to resist 600 atmos (up to 30 days to pass certification test), I think it reasonable to assume that the contents have survived even after all this time. However, I'm not so confident about the FADEC's and the other 12 or 13 subsystems with non-volitile memory devices which would have minimal, if at all, protection from pressure.
Given that this is a technical forum I wonder if one could explain the following:

How does 100-200gs on a persons body equate to G loadings on a CVR/FDR? innards

How does 200 atmos pressure at the bottom of the sea cause damage to a memory chip in a module if it is exposed to water intrusion?
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