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Old 30th Jul 2010, 02:21
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Mad (Flt) Scientist
 
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Originally Posted by Citation2
Mathematically speaking 1,23 Vs1g is higher than 1.3 Vs .

VSmin = 0.94 Vs1g . So take a calculator and work it out

Vref= 1.3 Vso = 1.3 X0.94 Vs1g =1.222 Vs1g

Airbus took 1,23 Vs1g
Sorry, that statement is not true for all types. The idea that Vs is about 0.94xVsr is an approximation based on looking at recent aircraft when the rule was being worked. There are aircraft where Vsr and Vs1g are much closer, and some further away.

Since FBW Airbuses in Normal Law are alpha protected, defining what Vsr actually is in terms of a "real aerodynamic stall" is quite an exercise in philosophy. You don't really get a traditional CLmax, you don't really get a Vsmin either. I believe all the FBW Airbuses have various kinds of "Special Conditions" to address the fact that the regs are written for an older techniology than now exists.
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