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Old 20th Jul 2011, 19:05
  #2079 (permalink)  
infrequentflyer789
 
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2. Due UAS, the autoPilot drops out, and a/c reverts to Alternate Law.
[..]

Protections would be better retained in condition 2, yes? Especially so since the a/s is not reliable, and ham handedness is more likely?
Protections or automatics ?

Protections, I'd say definitely not. bad things can (and have) happen when protections kick in on bad data (or on good data with design rules that turn out to be not so good). To engage protections based on known bad data would be poor design.

The protections are a line of defense at the edge of the envelope where you (auto or real pilot) shouldn't be going in normal flight anyway. It shouldn't matter if they aren't there if the plane is flown properly. Yes, that might be more of a problem with UAS + IMC + Turb etc., but it will be a lot more of a problem if the plane starts protecting you based on invalid data. Some UAS events have reported more or less simultaneous stall and overspeed warnings...


On the other hand, having a degraded A/P that held pitch and power (correct for altitude - assuming that's not dud data as well) and probably wings-level might actually be useful in some situations.
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