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Old 3rd Apr 2019, 22:28
  #3007 (permalink)  
GlobalNav
 
Join Date: Aug 2013
Location: Washington.
Age: 74
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Originally Posted by RatherBeFlying
It appears that MCAS can in ten seconds move the stab whenever it's in the mood, but the pilots need considerably longer to bring back the stab with dozens of cranks of manual trim - provided that airload allows them to move the trim.

Very much an unequal contest.

​​​​​​MCAS really shouldn't be putting in more trim than can be corrected by the crew in the interval before it reactivates.

But then, limiting MCAS authority might fail to achieve required stick force increase approaching stall. The software will have to get even fancier to satisfy 10E-9 reliability.

I'm with gums. Dump MCAS and fix the nacelle aerodynamics.
That's Design Assurance Level A. Does anyone here know what the DAL for this software actually is? As a previous poster said, it's no easy fix to make it so, if it's not DAL A.
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