Critical Angle of Attack:

✈️The coefficient of lift is a measure of how much lift the wing can produce and can only be changed by changing the shape of the wing or the angle of attack at which it cuts through the relative wind.

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✈️An increase in the angle of attack results in an increase in both lift and induced drag, up to a point. Too high an angle of attack (usually around 17 degrees) and the airflow across the upper surface of the aerofoil become detached, resulting in a loss of lift, otherwise known as a Stall.

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✈️The stall is defined as a sudden reduction in the lift generated by an aerofoil when the critical angle of attack is reached or exceeded.