TWICE AS FAR

 

SWISSAIR 111

CRASH INVESTIGATION

 

 

 

- EXTRACT FROM FILE NOTES -

 

 

FOR

- 2000 FEB 07 -

 

00-02-07          0700    Morning routine back at the hangar.  ..

            Gus described his usual method.  He normally embeds the bead in a plastic material to ease handling.  He then grinds off one side several microns deep and examines the surface under the SEM.  He then grinds away another couple of microns before re-examining the surface.  He continues this until the bead is totally used up.  It is a totally destructive method.  However, he cools the grinding process by water so that there is no heat damage one plus for the system.  I suggested that the Focused Ion Beam system would allow for numerous cuts, perhaps one-half or one millimetre apart, and he questioned the time involved as it is likely a very slow process, and therefore very expensive.  I asked him if he could determine the elements present on the ground surface, and he said that they do not usually do this.  I suggested that this was something that CANMET could easily do with the equipment that they have, providing a grid pattern of the slices to show the elements present and their location.  He suggested that it would be up to management to determine if they want to spend the money.  He also questioned if it was within the mandate of the TSB to conduct such tests to such an extent.  (It was later learned that FIB is not capable of cutting through the beads, but is simply used to slice out sections, as described in follow-up emails from Dr. BROWN added on 01-06-10)





 

 

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