Plane on a conveyor revisited Options

[james]

Dragging up the past a bit - TV show Mythbusters ran it's much anticipated episode with a practical experiment version of this question on it a couple of nights ago over in the US.

I don't know when it will come on over here but for the curious Kottke liveblogged it and also links to another good explanation from a guy with a Sc.D. in Nuclear Science and Engineering (whatever that is).

And for the hard of attention and understanding - yes of course it takes off.

[Jeffers]

Brando, Brando, Brando......

If you strapped a rocket to my arse when I was running on a treadmill and fired it up, it wouldn't matter if I were Linford Christie on Speed, I would be propelled forwards and out through the walls of the gym. If you nailed some wings to my shoulders, then I would probably be able to make some sort of attempt at flight.

There is no way the treadmill can stop the plane moving forward and gaining lift as the wheels are free spinning and reduce the opposing force needed to act against the thrust of the engines. The force supposedly generated by the treadmill.

If you took the wheels off the plane and just sat it on the treadmill and the friction generated by the treadmill was equal and opposite to the thrust generated by the engines, then the plane would just sit there burning jet fuel.


It would take off but not as some people imagine.
i.e... Just stationary and then magically lifting of the ground.


Jeff

This post has been edited by Jeffers: Feb 25 2008, 10:21 AM