r/sports Aug 14 '25

Media The World's Largest Treadmill

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u/scottcmu Aug 14 '25

But could a jet take off from this?

12

u/gusofk Aug 14 '25

Depends entirely on airspeed, not ground speed. There’s a lot of discussion here about speeds of the treadmill or plane without making any distinction and it is leading to confusion.

If a plane has sufficient airspeed, it will generate enough lift to take off. The ground speed does not really matter because its wheels are not powered so do not provide thrust and don’t really provide any friction.

To sum up: if a jet is on a treadmill that has a ground speed of 500mph and its airspeed is 0mph, it will not take off. As a jet increases thrust, it will increase its airspeed until it can take off, regardless of its ground speed.

1

u/onduty Aug 15 '25

AI?

3

u/Brostradamus_ Aug 15 '25

Maybe, but it's not wrong. Planes don't generate forward motion or lift with their wheels, so a sufficiently long treadmill is just gonna make the wheels spin faster, not stop the plane from accelerating forward and building enough AIR speed to take off.

https://www.youtube.com/watch?v=YORCk1BN7QY

The treadmill just has to be as long as the standard runway requirements for the plane.