Consider another body that requires airspeed to fly - a kite. If you were to run on a conveyor belt holding a kite, will the kite take off?

That's a difference in magnitude, not in principle. Look at this wind tunnel where model planes are tested (the planes are towed, like kites) -


They would fly up momentarily if you tug on the string (as this creates airflow against the kite, and subsequently lift), but unless you continue running backwards it will fall back down as it loses airflow/lift.

Try flying a small and heavy kite on a windless day. It's frustrating and your legs will get a good workout

If it generates thrust towards the hull, doesn't that create drag and result in force going in the backwards direction, working against the airplane?

And besides, the point of the conveyor is to match the airplane's forward speed but in the opposite direction, so "keep moving forward" won't happen unless the wheels loose frictional contact with the belt.

When it starts moving forward, the conveyer belt spins backwards faster (e.g. hook it up in a closed feedback loop), keeping the plane where it is.

How does the plane overcome this and move forward?

Thanks bgeh, I'm an ass for not reading your first post here, because it started with ".. doesn't take off .." and was freakin long. I now understand the importance of Aurora's statement that a car generates thrust into the ground while a plane generates thrust into the air, because when put together with freely-moving wheels it leads to the result that the conveyor belt can never hold a plane back*.

* - taking this at face value, in all honesty i am probably never going to cross-check with the equations coz i'm not a physicist