"Robert Barker" wrote in message

No, I can perhaps understand the misconception in non-pilots. But for a
pilot not to understand tells me he slept through a lot of his ground
school...

Or just hasn't thought it through fully. If you don't properly visualize
the experiment it's easy to think "Well, that's stupid. The airplane's not
going to take off from a conveyor belt because it's not going anywhere.
Otherwise, it would take off if you were sitting on the ground and applied
full throttle..."

....which, of course, is exactly what it does. ...just not where you've
parked it. The discussion must specifiy the length of the conveyor belt
because when I heard it I visualized a treadmill about the same length as
the airplane and thought the experiment was talking about VTOL.

-c