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Thread: CABLE vs FBW
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Old 11th Feb 2009, 09:23
  #64 (permalink)  
Lemurian

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FE Hoppy
You can take whatever definition of "stalling speed" you can, from any certification authority, you still cannot decide all by yourself that it describes the actual phenomenon called "stall" which is caused by complete airflow separation over the upper wing surface, i.e past the Clmax alpha, and is the start of uncontrolled flight.
For FBW airliners, the stall cannot be demonstrated, therefore the definition for stalling speed is taken from a spread of speeds, on a level flight (1 g) and during a descent (n< 1g).
The difference between certification definition and real life can be described with the example of that MD-82 that crashed uncontrolled in South America.
For a pilot, the recovery techniques from an actual aerodynamic full stall and an FBW airplane in "alpha prot" situation are very different, by some order of magnitude.
But I guess this discussion is about two different perspectives.
A stick pusher is not required if the aeroplane meets all the requirements as quoted above.
Tell that to Boeing and the UK CAA about the 727 certification (which ,in a slanted way proves my point about certification and handling perspectives).

Last edited by Lemurian; 11th Feb 2009 at 12:34.
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