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Discussion Starter #1
If an airplane is on a very long treadmill that matches its speed in the opposite direction, can the airplane take off?

The mythbusters finally put this one to rest. Dec 12, set your tivos!

PS, the answer is that the airplane will take off.
 

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Oh geez, not this, the infection has arrived, LOL.

The airplane will take off, I'm just waiting for the mythbusters to prove it.

If you can imagine a floatplane or seaplane taking off in a strong current, the resistance of the floats is far greater than wheel bearings, yet seaplanes can take off against the current.
 

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:confused: if I recall correctly, resistance increases as the square of speed, so as the airplane speeds up, resistance gets worse and worse. Water resistance is very high, so how can float planes take off at all?

I am thinking that they speed up and "plane" like a speedboat above the water, so they are really floating, not "plowing" through the water.
 

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This assumes that the aircraft can get moving in the first place. As the airplane speeds up, the treadmill matches its speed and it can't achieve forward motion and it can't get air flowing over it's wings.

So the airplane can't take off.
 

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ARRRRGGHH!

Float planes do take off so the resistance can't be too bad. Think of a rocket with wheels - the rocket will still move forward because the thrust can overcome the resistance of the wheel bearings, the only force moving back, the treadmill is not a factor.

An airplane has no drive wheels, the wheels are only free wheeling, so as the engine makes forward thrust, the treadmill is not a factor.

You can't confuse the speed of the treadmill with the speed of the airplane, they are not related. Even though the treadmill moves backward, it has no effect on the air above it and the speed of the airplane.
 

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I will put money on it....after Dec 12!

I think the airplane will take off. I have seen this myth before, here's how it makes sense to me: the airplane wheels are just freewheeling. Imagine a person on rollerskates on a treadmill. If you strapped a rocket to the rollerskates, ala wily e coyote, he will move even if the treadmill speeds up. The airplane will also begin to move when the engine makes thrust, as it accelerates it will gain lift and take off.
 

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Mythbusters is fun but it's only pop science so I'm sure there will be plenty of doubters out there.

I like Everest, beyond the limit and Survivorman. The sherpas do so much work that you have to be a super mountaineer to climb solo without oxygen, without sherpas putting in the ropes and ladders.
 

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Dirty Jobs FTW! The show has lost a lot of it's steam just because they've been running out of entertaining ideas but they still do a good job.

And the airplane will take off.
 

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Discussion Starter #10
!!!!!!!!!

I think when they said they were going to do the airplane-treadmill myth, that was also a myth.
 

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Lol, I guess the airplane takes off. The video proves it! I can't see any fault with how it was done, the airplane will take off.
 

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They've started playing commericals for it, it should air this wednesday. People are greatly anticipating it!
 

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Well, if you didn't see it, the airplane took off. Both scale tests and with a real airplane, it took off without a problem.

Video of the airplane taking off can be seen here:

http://www.youtube.com/watch?v=IbRcg3ji_Pc

They basically took a runway, put a very long tarp over it, and had a pickup pull the tarp in the opposite direction as the airplane moved forward.
 

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Very cool experiment!

But in the youtube comments, people are still crying foul. Some people don't get it even after they see it for themselves.
 
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