Plane vs. Conveyor belt.......old but interesting

[john970]

The question the mythbusters answer was modified to account for the spirit of the question (I got this off of a fan site):
"An airplane cannot take off from a runway which is moving backwards (like a treadmill) at a speed equal to its normal ground speed during takeoff."

"busted"

"First some small-scale tests were performed with a model airplane on a treadmill and the plane was able to take off. For the large-scale test, the MythBusters used a 400 pound ultralight aircraft with a 2000 foot tarp under it. The tarp was pulled backwards to simulate a moving runway. The ultralight pilot had no trouble taking off. This is because the thrust of the airplane engines acts on the air, not on the ground."

[Sherifftruman]

How there is any question about this I have no idea. Since planes develop thrust from engines and not from moving wheels on the ground, there is no way it will not take off.

Sure, a car could not take off, but a plane is not a car. :biggrin:

[B25 Jim]

Originally Posted by Sherifftruman

How there is any question about this I have no idea. Since planes develop thrust from engines and not from moving wheels on the ground, there is no way it will not take off.

Sure, a car could not take off, but a plane is not a car. :biggrin:

Not in Every case :wink:

Addition: For more current Aerocar Info, see here - http://www.strangebirds.com/SB-WU-Aerocar.html

[AwesomeBMW]

[Sherifftruman]

OK, I had recorded the Mythbusters episode and just watched it and man, that one ranks up there with their Escape from Alcatraz ep.

They definitively proved the myth as wrong using small scale and full scale tests, with a pilot who actually beleived the myth and was quite surprised the plane took off at all.

[ARES45]

You will take off, it is all about airspeed. The wheels are free-wheeling unless the brakes are on.