Can an airplane takeoff from a treadmill?

LongIslandIceSIP -

Let me take a crack at trying to explain this. The method of propulsion is key, because the plane is not pushed forward by using friction between the wheels and the ground. The wheels spin freely. The plane pushes on air to go forward, and the wheels aren't going to freely spin fast enough to compare to that force regardless of how fast the ground underneath is moving. Imagine the plane already flying in the air, with the wheels down. If you could spin those wheels with magic fingers, would it change how the plane was flying at all? Here's a different thought - what if the brakes were on, so that the wheels were down but not spinning -- would the plane fall out of the sky?

Going to your example 3, there is no way the 'paper' can match the forces of the 'magnet'. I'll try a variation on the rollerbalde analogy that has already been presented. You are on a treadmill, it's going really fast, you are on rollerblades. You can easily grip the siderails to pull yourself forward, regardless of how fast the treadmill is going, because you don't need to push off of the ground to go forward, you use the siderail to push forward. Your wheels are decoupled from your forward motion, they are irrelevant. For the plane, air is the siderail.
 
For those that want to see this in action, Mythbusters will be putting this to the test next week 12/12 in an airplane special. Here is the description from their website:

MythBusters
Air Plane Hour
TV-PG

Jamie and Adam take wing to test if a person with no flight training can safely land a 747 and if a plane can take off from a conveyor belt speeding in the opposite direction. Tory, Grant, and Kari jump on some Hollywood-inspired skydiving myths.

Link

Oops missed cottoneyed post above.
 
Yes, it's been answered. The conveyor belt can't spin fast enough to stop the plane from moving because it doesn't actually push on the plane at all -- it just spins the wheels. The plane pushes on air and moves forward with respect to the ground based on that force alone. A plane's wheels spin freely, and therefore the conveyor can't exert any significant backward force on the plane itself. The faster the conveyor goes, the faster the wheels spin, but that doesn't really affect the plane at all -- it stills moves forward with respect to the ground and takes off, given enough distance to reach the appropriate speed.
 
To quote one of your guys who posts on that other site that shall not be names:

The conveyor is moot!

And the VonSchleeden discussion got me to thinking about other engineering feats...namely, the turbo encabulator:

The Link
 
just found a post on the discovery forum where the MB producer says that the segment was shot and is scheduled to air 1/30/08 and that listing it on today's show was likely just a mistake.

In reply to:
 
the mythbusters episode should be on tonight, per commercials on disco and per my cable guide. i'm sure this will solve everything and put the debate to rest once and for all...
 
I wasn't sure the plane would take off after Adam accidentally ripped a bunch of holes in the treadmill, but the plane took off without too much trouble.
yippee.gif
 
OMG...I'm watching it right now. I can't believe the pilot said that.

It goes to show that just 'cause you learn what's in the manual, it doesn't necessarily mean you have any common sense.
 
True, but then again he was an ultralight pilot. Do they even require a license from the FAA??

I'm thinking ultralight pilots are the chiropractors of aviation.
 
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