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Old 12th Jul 2012, 17:01
  #296 (permalink)  
infrequentflyer789
 
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Originally Posted by syseng68k
If one assumes that the wind speed remains fairly constant
short term, such a baro inertial mixing scheme could be a valid
solution to the loss of air speed data, upon which so many other
subsystems depend.
There's your one teeny weeny problem right there. Wind speed might usually be fairly constant short term, but then pitots (properly heated) don't usually ice up either. Pitot icing is often in the vicinity of thunderstorms, and rapid changes in wind speed can be found... guess where.

In short, I think your scheme still has the common mode failure that the 3 redundant pitots have - the same external conditions may mess up the pitots and your inertial backup.

Additionally, you've now added another failure mode - if the pitot airspeeds vary wildly (but accurately) due to rapid air mass changes, is your inertial mixing going to vote out the correct data ?
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