will wrote:
This is where I diverge with "scientists" who live in academic ivory towers without regard for plain common sense. You're talking about two different planes of motion...the "runway", or in this case, the treadmill, and the air passing under, or in this case, sitting motionless around the wings. While one plane may provide the theoretical force required to generate enough momentum to allow liftoff, it's the air speed, not the ground speed, that is what generates enough uplift to propel the object vertically at a rate greater than the downward force of gravity. But, since no air is moving--only the treadmill--no vertical force is generated...only horizontal. Think of this in more than one plane. By reducing this to a single variable (horizontal velocity) the problem becomes unrealistic and cannot truly echo an actual case.
GODDAMMIT!! ANSWER THE QUESTION! WHAT FORCE IS KEEPING THE PLANE FROM MOVING??
Here's an analogy. You know those conveyor belt-walkway things in airports? What if you put a jet pack on your back and got on a skateboard on the conveyor? No matter what speed the conveyor is going, you could certainly counter act the ROLLING RESISTANCE AND FRICTION with a jetpack, right? It's the same think here!!
You are the one confusing the reference frames!! Air will move over the wings of the airplane because the airplane can move forward relative to the ground no matter how fast the freakin' treadmill is spinning!! The spinning treadmill will only make the wheels go faster and will impart no significant force on the airplane!!!
No please stop making a fool of yourself! Don't you know this message board is archived for posterity?