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"Airplane On Treadmill" solved by Mythbusters.
The short answer is that a treadmill can't prevent a plane from moving forward, and thus can't prevent it from taking off.
Detailed explanation: 1) Picture a car. What is its drive train? The engine creates torque which is transmitted to the axles and turn the tires which provide forward or reverse momentum through friction with the ground. Thus the car moves. On a treadmill, this momentum would be counteracted and thus you could "force" the car to not move.
2) An airplane's drive train is solely contained in a space above the ground. That is, the propeller produces THRUST through the air which moves the airplane forward and in turn provides airflow across the wings which provides lift. NOTICE that the ground and friction are NOT mentioned here.
3) The ONLY reason for the wheels on an airplane is to keep the airplane's belly from being scratched up. That is the wheels and the legs elevate the body above the ground to a space where the airplane's drivetrain is effective (in the air).
So let's set up the scenario, a plane is on a treadmill that is EXACTLY matching the virtual ground speed of the airplane. The ground speed of the airplane is 0 (ZERO). However, what is the air speed (the speed of the air moving over the wings)? At this point we don't know, but we do know that the ground speed is NOT RELATIVE to the air speed. If it were, then the engine would have to be connected to the wheels. Any increase in propeller rotation will increase thrust, which will increase the air flow over the wings, which will provide lift. Thus the airplane flies. Think of it this way: After a plane takes off and stows its wheels, why doesn't it come to a grinding halt? The ground speed of the wheels is 0 (ZERO), the same as when it was on the treadmill. Source: Mythbusters-Wiki
Detailed explanation: 1) Picture a car. What is its drive train? The engine creates torque which is transmitted to the axles and turn the tires which provide forward or reverse momentum through friction with the ground. Thus the car moves. On a treadmill, this momentum would be counteracted and thus you could "force" the car to not move.
2) An airplane's drive train is solely contained in a space above the ground. That is, the propeller produces THRUST through the air which moves the airplane forward and in turn provides airflow across the wings which provides lift. NOTICE that the ground and friction are NOT mentioned here.
3) The ONLY reason for the wheels on an airplane is to keep the airplane's belly from being scratched up. That is the wheels and the legs elevate the body above the ground to a space where the airplane's drivetrain is effective (in the air).
So let's set up the scenario, a plane is on a treadmill that is EXACTLY matching the virtual ground speed of the airplane. The ground speed of the airplane is 0 (ZERO). However, what is the air speed (the speed of the air moving over the wings)? At this point we don't know, but we do know that the ground speed is NOT RELATIVE to the air speed. If it were, then the engine would have to be connected to the wheels. Any increase in propeller rotation will increase thrust, which will increase the air flow over the wings, which will provide lift. Thus the airplane flies. Think of it this way: After a plane takes off and stows its wheels, why doesn't it come to a grinding halt? The ground speed of the wheels is 0 (ZERO), the same as when it was on the treadmill. Source: Mythbusters-Wiki
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