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How does CAS, IAS, TAS stall speed changes?

Asked by: 4623 views Aerodynamics, Private Pilot

I recently read an article stating that one of two type of stall speed(IAS, CAS, TAS) will never change with altitude.

From my understanding,  as we go up, there are lesser air molecules so when you exceed the critical angle of attack, the registered IAS is lesser than that of lower altitude.

Could anyone offer an scientific idea on how each type of airspeed readings change ?

Thanks.

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2 Answers

  1. Best Answer


    David George on Oct 05, 2017

    Think of IAS as purely dynamic pressure (the aerodynamic equivalent of kinetic energy). A plane stalls at the same IAS because it is just a reference of dynamic pressure acting upon the airfoil. TAS stall speed will of course therefore increase with altitude.

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  2. Actuator on Oct 07, 2017

    could you give me more explanation with what dynamic pressure means over the wing and what it has to do with readings on ASI?

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