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Old 7th April 2012 | 10:51
  #1307 (permalink)  
HazelNuts39
 
Joined: Jul 2009
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From: France - mostly
Originally Posted by Diagnostic
"This is a UAS situation, all my pitot probe pressures are different so I have to disconnect the AP - recommend you fly pitch & power which for this alt is X/Y"
The trigger was that the system detected a sudden drop in one of the three airspeed values. The "all pitot probe pressures are different" occurred much later at 2:12:xx when the ADR DISAGREE message was generated.

Thirty knots drop of IAS in one second is not sufficient to identify UAS. It is not inconceivable that it would occur as a real change of airspeed in a windshear/downburst close to the ground or in the vicinity of the jetstream at altitude. Considering the multitude of possible causes and flight conditions, IMHO the computers cannot reliably identify UAS, but must leave the diagnosis of the problem to intelligent humans.

P.S. Sorry Clandestino, cross-posted

Last edited by HazelNuts39; 7th April 2012 at 11:40. Reason: P.S.
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