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Old 5th Dec 2018, 18:08
  #1996 (permalink)  
climber314
 
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Originally Posted by WillFlyForCheese
I see lots of folks assuming MCAS trims 2.5ND each time - but that's not what I get from the description of MCAS, which provides: Stabilizer incremental commands are limited to 2.5 degrees and are provided at a rate of 0.27 degrees per second. The magnitude of the stabilizer input is lower at high Mach number and greater at low Mach numbers.

So - depending on speed and AoA, MCAS will trim up to 2.5ND - correct? Or - is there something else that confirms MCAS trimmed JT610 2.5ND repeatedly, and then continuously?
True but we're discussing a specific type of failure where the AoA is incorrect causing the software to say "NoseDown" to MCAS constantly. In this failure it seems that MCAS will indeed run to the full 2.5 degrees. In other situations it would be as needed up to 2.5 degrees. The "reset" mentioned is interesting because it seems to fit the Stab Trim pattern we see in the FDR chart(s).
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