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Old 7th Aug 2011, 16:18
  #1739 (permalink)  
rudderrudderrat
 
Join Date: Oct 2009
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Hi DozyWannabe,

You made an interesting observation about pilot instrument scan and I agree with you:
…it is likely that the computers will know more about the plethora of aircraft parameters at any given time than the pilots, who are relying on an instrument scan and therefore only a subset of available data at any given time.
but I disagree about the help the automatics will give:
In essence, when you get ADR DISAGREE and Alt 2 clicks in, the computers are saying to the pilot "I can't trust these readings and I don't have your problem-solving skills. You can not only see the instruments but can also see outside. I'll help you keep the shiny side up based on what I know, but if I'm wrong you can override me".
So the pilot only has a subset of available data with UAS, he does not have the benefit Longitudinal speed stability in ALT2 Law, he has to keep it shiny side up himself with Roll Direct (which he appears to have found "very twitchy"), and the auto trim is silently trimming the load from the up elevator well beyond alpha max.
What a magnificent design!
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