...do you notice that in the website you posted, the velocities are always described as "relative to the ground", "velocity of the plane relative to an observer on the ground", "its speed with respect to an observer on the shore", and so on? No mention of velocity with respect to the air rather than airspeed, always referred to an observer "on the ground".
Any bells going off?
Anything?... ...Anybody?... ...Beuler? Ferris Beuler?