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Old 30th Dec 2016, 14:07
  #32 (permalink)  
PDR1
 
Join Date: Nov 2015
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Originally Posted by Concours77
" wings do not stall at a speed; they stall at an angle. So if AoA is used it is to give the driver access to the prime information, not as a substitute for airspeed."

An aircraft stalls at Vs. that is a velocity, which infers angle of attack.
The point is that the airspeed "Vs" varies with weight, altitude, normal acceleration and lots of other parameters. The stalling AoA remains essentially constant, changing only slightly with air density. So for any given wing configuration (flap/slat setting) you can rely on remaining clear of the stall using the AoA gauge directly, whereas to use the ASI you will need to refer to calculated or tabulated data to produce estimates based on the known and assumed state of the aeroplane.
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