Quote:
Originally Posted by clevalley  Air moves over the airfoil by the plane moving forward. If the engines are providing thrust to move the plane @ 500 MPH, but a device under it was spinning at 500 MPH the net gain/movement of the place would be 0MPH - thus NO airflow over the airfoil, this would equal 0 lift.
Now, if the engines exceeded the forward moment of 500+ MPH, then the plane would move forward which causes air to flow over the airfoil - whatever the minimum speed for take-off/lift would be would be needed to be added to the delta baseline of 500MPH plane speed to achieve lift in the above scenario.  |
your theory is only good if the thrust to move the plane is applied to the wheels.
but its not.
In your theory, as soon as a plane took off it would land again because it lost thrust when the wheels left the ground.