#Angle of Attack

=an acute angle “A”
=the angle between chord line and relatively wind

#Stall
When there is a critical Angle of attack,
lift is destroyed and  no longer air conforms on the surfce of the wing.

ex)The angle of attack at which an airplane wing stalls will remain the same regardless of gross weight

ex)The indicated airspeed at wich a given airplane stalls will remain the same regardless of altitude.

ex)At hight altitude the stall speed is the same.