yeah I know…
Isn’t it all about the air going over the wings? The plane doesn’t care what the ground is doing.
I cannot click links because of hackers - what does it say?
I clicked the link. It requested my social security number and the numbers from the bottom of one of my checks. I entered the required information and await a reply. Will let you know what they say.
Not surprisingly, it says that yes, the plane will take off.
An airplane can only take off from a moving runway if you pay a Nigerian prince first.
are people still talking about this?
airplanes are not cars. they don’t push against the ground in order to move. whatever the ground is doing is irrelevant to the thrust being generated by the engines.
Sure, if you grip it by the husk.
Not entirely irrelevant, there could be enough friction to prevent it from building up speed. Try taking off in sand or mud.
Planes take off from aircraft carriers all the time - that’s a moving runway!!
Yes, although wheels on a moving runway won’t bog down like in sand or mud, I do think other factors might come into play. Get the wheels spinning fast enough (as if the runway is moving backwards at hundreds of miles per hour) and the tires will break apart, for example.
It says the only word not in the dictionary is “gullible”. I’m sure you can verify that for us.
The link is itself a link to Cecil’s controversial column about a plane taking off from a treadmill and no fewer than 19 threads where the question has been argued.
The short answer is: Cecil says yes.
Only if you pick the treadmill behind the second door.
What if 1920’s style death-ray?
It helps if the runway is moving in the direction the plane is trying to take off.
yeah, this. there’s only really two ways to approach it:
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if we’re in ideal/“spherical cow” world (as the question is usually asked,) the treadmill/runway can accelerate nearly instantaneously and run at infinite speed. therefore, we need to treat the airplane’s wheels as entirely frictionless. in which case the moving runway/treadmill cannot exert any force on the plane and therefore cannot impede its movement.
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if we’re in real world, the treadmill/runway cannot accelerate instantaneously nor achieve infinite speed. Further, there is the rolling friction of the tires and the drag of the wheel bearings. In this case, it’s a matter of whether the plane can accelerate quickly enough to achieve takeoff speed before the tires are being spun faster than they can handle and explode.
Mythbusters actually did this one and they proved, yes, it could.
Except if we’re in the real world, you can’t build a treadmill that can spin an airplane’s wheels so fast they explode. This is the theory that the treadmill can spin arbitrarily fast, and it is controlled to spin as fast as necessary to prevent the airplane from moving forward. How this is supposed to work in a real physical treadmill is unclear.
If all we do is move the treadmill surface as fast backward as the plane is moving forward, then the plane takes off easily since all that happens is the free-spinning wheels are spinning twice as fast, as was demonstrated on Mythbusters.