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Old 7th May 2010, 23:00
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DenisG
 
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Also at 2.11h, from BEA-AF447-Interim Report-17-DEC-2009, p. 37

ISIS (22FN-10FC) SPEED OR MACH FUNCTION (2 h 11)
  • a CAS higher than 530 kt without the Mach value exceeding 1. This
    condition implies that the aircraft was at an altitude comprised between
    about 4,000 and 14,000 ft;

Could somebody explain to me, why it can be derived that this can only have occurred between 4,000 and 14,000 feet? Why not lower or higher? And why then still so unspecific?

To mm43:
  • "at 2 h 10 min 34, the last position received was latitude +2.98° (North) and longitude -030.59° (West)" (BEA-AF447-Interim Report-02-JU-2009, p.48) or to us 'last known position'.
  • Still, the first 4 ACARS occurred in the 20 seconds before this position, including TCAS off.
  • After that we have receiced the above speed or mach function, implying that the a/c was already pretty low at this point (between 4,000 and 14,000 feet, at 02.10.54h), making the slowest average decline guess at around 60 feet per second after that.

Q: This also means that the decline must have begun before the first TCAS messages arrived at 02.10h, right?

Thx.
Denis

Last edited by DenisG; 7th May 2010 at 23:10.
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