so if youre going 500kph but sending wind backwards 450 kph something doesnt fit here
on the other hand if you considered the air of imagined visocity 1, the maximum, the propeller would just work as a cork screw
also theres the antinewton concept of propeller lift, wouldn the vacuum suck?
also ill mention that this picture contradicts newton since no wind is sent down but the plane still gets vertical force:
http://upload.wikimedia.org/wikipedi...ortex_edit.jpg