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Old 21st Aug 2014, 22:53
  #288 (permalink)  
DozyWannabe
 
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Are "longitudinal static stability" and "low speed stability" one and the same thing then? It may be, and you may be right, but I'm not 100% sure.

The wording is a little vague - it does not state what happens when the three ADRs come back online. I was pretty sure that it would bring the soft protections back, but I could be wrong.

[EDIT : This link : http://webcache.googleusercontent.co...&ct=clnk&gl=uk

seems to suggest that Low Speed Stability is lost in the event of double or triple ADR failure, but I'm having trouble finding material confirming what happens when the ADRs come back online. I'm *guessing* that "longitudinal static stability" in the context of the FCTM is referring to the requirements of restoring High AoA Protection mode (and thus Normal Law), but I admit it'd definitely be handy to know for sure. ]

[EDIT 2 :
Originally Posted by RetiredF4
but this did not happen as all three ADR's were rejected simultaneously.
Originally Posted by BEA Interim Report 3 (EN) 1.16.4.1
At 2 h 10 min 08, the two flight directors disappeared and auto-thrust was lost. This time interval was probably due to the fact that the three ADR were not rejected at the same time in the two FMGEC.
(I must say that the Final Report seems to drop some useful background info from the 3rd Interim, and the wording regarding Alt 2B is a bit sketchy in places - though if it is correct in that 2B denotes loss of low speed stability, and that the law never changed from 2B, then you're right - and it was missing, my apologies.)
]

Last edited by DozyWannabe; 21st Aug 2014 at 23:40.
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