Quote:
Originally posted by Timmah:
The thrust provided by the engines is independent of the wheels. It doesn't even have to be wheels most of you guys are caught up on that. What if the plane was floating on a pocket of air like an airboat. What does thrust care what the ground is doing? The ground/conveyor could be traveling at a 100 MPH and it would not affect the floating plane right? OK so lets start the engines and create some thrust. What happens to the plane then? It moves forward at a gradually increasing speeed, generates lift and takes off.

If you think about it the planet is a big ass conveyor traveling/spinning at thousands of miles per hour. According to you guys we would never be able to take off.
I just added something to my post above so you missed it. It DOES matter what the tires do because they're attached to the plane. Here's my addition:

Distance traveled equals 2πR, where R is the wheel's radius. Let's just say the answer to that equation in our scenario is 12 feet. But the treadmill moves 12 feet in the opposite direction. The tires are attached to the plane, we can all agree on that, right? So if:

2πR = 12 feet but treadmill motion = -12 feet then the resulting forward motion is ZERO.

For the plane to move forward, 2πR MUST be greater than the distance the treadmill moves backward, but the scenario says the belt matches the plane's speed, so the result can't be greater than zero.

On a runway of course, there's no counter-motion backwards so 2πR is always greater than zero, resulting in forward motion.

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And you didn't do what I asked - FORGET the method of propulsion because it DOESN'T MATTER.