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Old 18th Mar 2019, 10:58
  #1884 (permalink)  
infrequentflyer789
 
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Originally Posted by FCeng84
Thoughts on Seattle Times article published Sunday morning Seattle time

This article is generally well written and seems quite accurate.
Interesting as I think Boeing described it as "mis-characterisation"... I thought (having less other info to corroborate it, I suspect) it was plausible and made sense, your clarification makes a lot of sense too.

Question: If MCAS has (sort of) a speed-dependent "gain", what value does it use when airspeed/mach is unknown (or known-bad)? Does it, perhaps, use the higher value (more trim) to be "safe"?

The accident flights and the made-it-back Lion previous flight all reported unreliable airspeed as first problem. I don't think airspeed is voted on 737, although there are three pitot/statics one set is used for standby only so at the FCCs airspeed must be either known (two inputs agree) or unknown (disagree). Have I got that right?
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