Quote Originally Posted by Interlude
Oh okay,

but I was NOT talking in the sense that your car is in neutral + jet engine, no, not that.

I was talking about the plane's wheels = the same as the dyno's rollers.
And the treadmill = the car itself.

Lift up or not is based on air pressure. if there aren't any, plane will not lift off. Also, the treadmill will adjusting its negative velocity accordingly to the plane's.

Using the car vs dyno was a bad example. It was only to show you that the treadmill does output torque and HP in negative X direction to cancel out the free rolling velocity in positive X direction.
HOW is it cancelling the forward velocity, though?

Answer these questions for me:
- The treadmill is only spinning the wheels of the plane, yes?
- The wheels of the plane are free rolling, yes?
- Can spinning free rolling wheels cancel out the forward velocity of the plane?

I want you to think about that last question really hard... It actually makes the wheels spin faster. Look below: