Here, try this.
1. Put on some rollerskates. Rollerblades will work as well. Do not try this with ice skates.
2. Stand on a treadmill. Turn it on. See how the treadmill spins up, and you remain stationary?
3. Elevate the rear of the treadmill, so that you're going downhill. Do you start to move forward? Of course you do, regardless of how fast the treadmill is going. Gravity pulls you downward to the bottom of the slope.
The kicker behind this internet question of myth and legend is that the treadmill doesn't make a bit of difference. The treadmill is effectively disconnected from the power/thrust generating part of the airplane - its jets - so it doesn't matter how fast the treadmill goes. The airplane moves forward, the wheels canceling any rearward force generated by the treadmill.
Let's repeat that, since it's important: The airplane moves forward, the wheels canceling any rearward force generated by the treadmill.
1. Put on some rollerskates. Rollerblades will work as well. Do not try this with ice skates.
2. Stand on a treadmill. Turn it on. See how the treadmill spins up, and you remain stationary?
3. Elevate the rear of the treadmill, so that you're going downhill. Do you start to move forward? Of course you do, regardless of how fast the treadmill is going. Gravity pulls you downward to the bottom of the slope.
The kicker behind this internet question of myth and legend is that the treadmill doesn't make a bit of difference. The treadmill is effectively disconnected from the power/thrust generating part of the airplane - its jets - so it doesn't matter how fast the treadmill goes. The airplane moves forward, the wheels canceling any rearward force generated by the treadmill.
Let's repeat that, since it's important: The airplane moves forward, the wheels canceling any rearward force generated by the treadmill.